CN105466355B - Portable train wheel tread contour detecting device - Google Patents

Abstract

The invention discloses a portable detection device for measuring the tread profile of train wheels. The invention can realize high-precision and rapid measurement of wheel tread wear. The present invention is realized through the following technical solutions: the screw is driven by a stepping motor to move the nut along the axis of the wheel; the movement of the nut drives the laser displacement sensor in the plane of the wheel axle through the V-shaped ball guide rail and the profiling motion mechanism Do two-dimensional motion, and its motion trajectory imitates the standard tread profile of the wheel, so as to realize point-by-point scanning measurement of the tread profile. Due to the realization of profiling measurement, only a sensor with a small measurement range can be used to meet the measurement requirements of the entire tread profile, the measurement accuracy and resolution are higher, and the appearance size of the instrument is smaller. The inclined installation design of the sensor is adopted to solve the problem that the measurement accuracy is reduced or even impossible to measure due to the excessive angle between the measuring beam and the normal line of the measured point where the slope of the tread profile curve is large.

Description

Portable Train Wheel Tread Profile Detection Device

technical field

The invention relates to a portable device for detecting the tread profile of a train wheel, which can quickly detect the wear condition of the wheel tread, so as to meet the needs of the development of high-speed railways for the detection instrument of the wheel tread.

Background technique

With the development of high-speed railways, the speed of trains has increased significantly, and operations such as sudden acceleration, deceleration, and emergency braking have become more frequent, resulting in increased wear between the wheels and rails. Therefore, it is necessary to regularly detect the wear of the wheel treads. Therefore, there is an urgent need for a wheel tread testing instrument that is miniaturized, intelligent, and has high detection accuracy and detection efficiency.

At present, there are two main types of wheel tread wear detection methods: one is manual measurement using contact detection tools, which has low detection efficiency and large errors. The second is the non-contact measurement (optical scanning and optical imaging) method, which has high measurement efficiency and can realize automatic detection. Among them, the measurement method using the laser displacement sensor has the greatest potential for miniaturization, intelligence, and improvement of measurement accuracy and efficiency. However, in the existing measuring instruments, the laser displacement sensor uses a linear motion measurement method, and a sensor with a large effective measurement range must be used, resulting in low measurement resolution (the measurement resolution of the laser displacement sensor decreases with the increase of its measurement range. ). Moreover, the sensor is installed in such a way that the outgoing beam of the sensor is perpendicular to the axis of the measured wheel (that is, perpendicular to the measuring motion direction of the sensor), resulting in the difference between the measuring beam and the normal of the measured point where the slope of the tread profile curve is large. If the included angle is too large, the light spot projected by the measuring beam onto the surface to be measured will be severely scattered, resulting in a significant decrease in measurement accuracy and even measurement distortion. The present invention aims to solve the above problems, and designs and manufactures a portable and intelligent wheel tread detection instrument.

Contents of the invention

The invention provides a design scheme of a portable train wheel tread detection device. The scheme combines the profiling measurement technology with the laser displacement sensor, which not only reduces the requirements for the sensor's measurement range, but also solves the problem of low measurement accuracy or even distortion where the slope of the wheel tread contour curve is large.

The technical scheme that the present invention takes is:

A portable train wheel tread profile detection device, including a laser displacement sensor and its mounting frame, a stepper motor and its controller, a ball screw nut pair, a profiling motion mechanism including a standard tread profile profiling guide rail, and a V-shaped ball guide rail , single-chip microcomputer and measurement control and display; its characteristics are: the stepping motor drives the ball screw, and the nut makes a linear motion; the movement of the nut transmits the force to the sensor mounting frame through the V-shaped ball guide rail, and the mounting frame plays the role of the profiling motion mechanism Next, with the movement of the nut, it can move along the direction perpendicular to the movement of the nut, so that the movement trajectory of the laser displacement sensor installed on it can follow the standard tread profile of the wheel; the single-chip microcomputer collects the output signal of the laser displacement sensor, and the tread surface is obtained through data processing. Profile measurement results.

Further, the profiling motion mechanism is composed of a standard tread profile profiling guide rail, a V-shaped ball guide rail, a sensor mounting frame and a bearing; the feature is that the V-shaped ball guide rail is installed on the slider and the sensor that are fixedly connected with the nut. Between the mounting frames, the power is transmitted to the sensor mounting frame; the two bearings fixed on both sides of the sensor mounting frame roll along the standard tread contour profiling guide rail to realize the profiling measurement movement of the laser displacement sensor.

Further, the laser displacement sensor is installed at an angle α inclined to the movement direction of the nut, so that the output beam of the laser displacement sensor is obliquely incident on the measured surface.

Further, the motion driving part is composed of a hybrid stepper motor, a coupling, a ball screw, a nut, a slider, a bearing seat, and a limiter guide rod; the characteristics are: the coupling meets zero backlash; the limiter The guide rod is slidably matched with the light hole on the slider, and the limit nut can only move in a straight line.

Further, the installation of the profiling motion mechanism and the motion driving mechanism is based on the column plate; a flat magnet is fixed on the side of the column plate, and the inner positioning surface of the wheel is sucked tightly during measurement as a horizontal measurement reference plane; two magnets are fixed on the side of the column plate. The root positioning cylinder is close to the rim when measuring, and is used for vertical positioning.

Furthermore, the standard tread profile profiling guide rail part is composed of two identical guide rails; the feature is that: the two standard tread profile profiling guide rails are simultaneously used as supporting components of the profiling motion mechanism, reducing the structural size and weight.

(1) The profiling motion mechanism is composed of a slider firmly connected with a nut, a V-shaped ball guide rail, a sensor mounting frame, a bearing and a standard tread profile profiling guide rail. The V-shaped ball guide rail is installed between the slider and the sensor mounting frame, and the power is transmitted to the sensor mounting frame; the two bearings fixed on both sides of the mounting frame roll along the standard tread contour profiling guide rail to realize the profiling movement of the mounting frame , only need to use a sensor with a small effective measurement range to achieve full-range measurement.

(2) The laser displacement sensor is installed at an angle α oblique to the direction of movement of the nut (the axis of the measured wheel), so that the output beam of the sensor is obliquely incident on the surface to be measured, so as to solve the problem that the measurement accuracy is reduced where the slope of the tread profile curve is large. Problems that cannot even be measured.

(3) The motion driving part is composed of a hybrid stepper motor, a coupling, a ball screw, a nut, a slider, a bearing seat, and a stop guide rod; the coupling meets zero backlash, and the stop guide rod and the slider The light hole on the top is a sliding fit, limiting the movement of the nut only in a straight line.

(4) In order to ensure the compact structure and strong integrity of the device, the installation of the profiling motion mechanism and the motion driving mechanism is based on the column plate; the standard tread profile profiling guide rail part is composed of two identical guide rails, and the two The standard tread contour profiling guide rail is also used as a supporting part of the profiling motion mechanism, reducing the size and weight of the structure.

(5) A flat magnet is fixed on the side of the column plate, and the inner positioning surface of the wheel is sucked tightly as the horizontal measurement reference plane during measurement; two positioning cylinders are also fixed on the side of the column plate, which are close to the wheel rim during measurement for vertical positioning . This structural design makes the instrument compact in structure and strong in integrity.

(6) Embedded design is adopted, the output signal of the sensor is collected by the single-chip microcomputer, the measurement result of the tread profile is obtained through data processing, and the output is displayed or stored.

Beneficial effects of the present invention:

(1) Since the measurement trajectory of the laser displacement sensor follows the standard wheel tread profile, only a sensor with a small effective measurement range (±5mm) can be used to detect the entire wheel tread profile, which not only improves the measurement accuracy and resolution, but also Moreover, the detection device has a more compact, portable and portable structure.

(2) The laser displacement sensor is installed at a certain angle α to the movement direction of the nut (the axis of the measured wheel), which solves the problem that the angle between the incident beam and the normal line of the measured point is too large in places where the slope of the tread profile curve is large. As a result, the spot of the incident light beam projected on the surface to be measured is severely scattered, resulting in a decrease in measurement accuracy or even a problem of being impossible to measure.

(3) The use of V-shaped ball guide rails can minimize the influence of friction generated during the profiling movement on the transmission of the screw and nut, and the movement is light.

(4) The ball screw nut is used to drive, which not only reduces the wear of the screw, but also requires a small driving torque. It can be driven by a micro stepping motor to reduce the overall size of the device.

(5) The structural design of the device has a strong integrity and a compact layout, which can reduce the overall size and weight of the device.

Description of drawings

Fig. 1 is the overall structure front view of the present invention;

Fig. 2 is A-A sectional view;

Figure 3 is a top view of the overall structure;

Fig. 4 is a B-B sectional view.

detailed description

Further illustrate the present invention below in conjunction with accompanying drawing.

As shown in Figures 1 to 4, the stepper motor 1 is installed on the support base 2, and drives the lead screw 4 through the coupling 3; the nut 5 is fixedly connected with the slider 6, and the light hole on the slider 6 is connected The moving guide rod 7 is slidably matched, and the limit nut 5 can only move in a straight line; V-shaped ball guide rails 9 and 10 are installed between the two sides of the slider 6 and the inner sides of the left and right columns of the sensor mounting frame 8, so that the sensor mounting frame 8 can be moved up and down. Movement; the outer sides of the left and right columns of the mounting frame 8 are respectively equipped with bearings 11 and 12; the two bearings roll along the standard tread contour profiling guide rails 13 and 14 respectively. When the slider 6 (connected with the nut 5) moves linearly, the force is transmitted to the sensor mounting frame 8 through the V-shaped ball guide rails 9 and 10, so that the two bearings roll along the standard tread profile profiling guide rails 13 and 14 respectively. , so that the sensor mounting frame 8 moves along the direction perpendicular to the movement of the nut 5 while moving linearly with the slider, so as to realize the profiling of the standard tread profile of the wheel.

The installation of profiling kinematic mechanism and motion drive mechanism is based on column plate 15. A flat magnet 16 is fixed on the side of the column plate, and the positioning surface inside the wheel is sucked tightly as the horizontal measurement reference plane during measurement; two positioning cylinders 17 and 18 are also fixed on the side of the column plate, which are close to the wheel rim during measurement and used as the vertical direction. position. The motor support base 2 is connected to the column plate 15; two standard tread contour profiled guide rails 13 and 14 are symmetrically connected to the column plate 15 as the main supporting part of the instrument structure, making the structure compact, light and handy, and strong in integrity. The laser displacement sensor 19 is installed on the sensor bracket 20 , and the bracket 20 is then fixed on the sensor mounting frame 8 .

Claims (6)

1. A portable train wheel tread profile detection device, including a laser displacement sensor and its mounting frame, a stepper motor and its controller, a ball screw nut pair, a profiling motion mechanism including a standard tread profile profiling guide rail, and a V-shaped Ball guide rail, single-chip microcomputer and measurement control and display; its characteristics are: the stepping motor drives the ball screw, and the nut makes linear motion; the movement of the nut transmits the force to the sensor mounting frame through the V-shaped ball rail, and the mounting frame is in the profiling motion mechanism Under the action of the nut, it can move along the direction perpendicular to the movement of the nut at the same time, so that the movement track of the laser displacement sensor installed on it can follow the standard tread profile of the wheel; the single-chip computer collects the output signal of the laser displacement sensor, and after data processing Obtain tread profile measurements. 2. The portable train wheel tread profile detection device according to claim 1, wherein the profiling motion mechanism is composed of a standard tread profile profiling guide rail, a V-shaped ball guide rail, a sensor mounting frame and a bearing; it is characterized in that: V-shaped balls The guide rail is installed between the slider and the sensor mounting frame fixedly connected with the nut, and transmits the power to the sensor mounting frame; the two bearings fixed on both sides of the sensor mounting frame roll along the standard tread contour profiling guide rail to realize laser Profiling of displacement sensors measures motion. 3. The portable train wheel tread profile detection device according to claim 1, wherein the laser displacement sensor is installed at an angle α inclined to the direction of motion of the nut, so that the outgoing beam of the laser displacement sensor is obliquely incident on the measured surface. 4. The portable train wheel tread profile detection device according to claim 1, wherein the motion drive part is made up of a hybrid stepper motor, a shaft coupling, a ball screw, a nut, a slider, a bearing block, and a stop guide rod; Its features are: the coupling meets zero backlash; the limit guide rod is slidingly matched with the light hole on the slider, and the limit nut can only move in a straight line. 5. The portable train wheel tread profile detection device according to claim 1, wherein the installation of the profiling motion mechanism and the motion drive mechanism is based on the column plate; a flat magnet is fixed on the side of the column plate, and the inner side of the wheel is sucked tightly during measurement The positioning surface is used as a horizontal measurement reference plane; two positioning cylinders are also fixed on the side of the column plate, which are close to the wheel rim during measurement for vertical positioning. 6. The portable train wheel tread profile detection device according to claim 2, wherein the standard tread profile profiling guide rail part is composed of two identical guide rails; it is characterized in that: two standard tread profile profiling guide rails are simultaneously used as imitation The supporting part of the shape kinematic mechanism reduces the structural size and weight.