Rack shaft comprehensive error detection device

Abstract

A rack shaft comprehensive error detection device relates to the technical field of mechanical part detection, and comprises a standard gear, the tooth profile parameters of which are manufactured based on the technical parameters of a paired gear of a rack to be detected; the driving mechanism is used for driving the standard gear to be meshed with the tested rack and to do reciprocating motion; the sensor system comprises a displacement sensor and an angle sensor and is used for detecting the displacement variable quantity and the angle variable quantity of the rack to be detected in the reciprocating motion in real time; the data processing unit is in communication connection with the sensor system and is used for converting the displacement and angle variation into radial comprehensive error data; and the display unit is used for outputting the detection result of the radial comprehensive error. According to the utility model, through simulation of real meshing and multi-sensor detection, the technical bottlenecks of low efficiency, poor precision and large man-made interference in traditional rack detection are overcome, and a reliable quality control means is provided for large-scale production of high-precision racks.

Description

Technical Field

[0001] This utility model relates to the field of mechanical parts testing technology, and in particular to a rack shaft comprehensive error testing device. Background Technology

[0002] In the field of mechanical transmission, racks are core components of precision transmission systems such as steering gears, and their machining accuracy directly affects assembly torque fluctuations and equipment operational stability. Key characteristic parameters of racks include radial total deviation (Fi"), radial total deviation (fi"), radial runout (Fr"), center distance deviation, and variation in span distance M. The detection of these parameters is a crucial step in ensuring the meshing performance of the rack and its mating gear.

[0003] Currently, the industry mainly relies on the following traditional methods for detecting key characteristics of racks:

[0004] 1. Coordinate Measuring Machine (CMM) Inspection: Used to measure radial composite deviation (Fi", fi") and center distance deviation (△a). During operation, the rack needs to be positioned and clamped using a V-block, establishing a coordinate system with the end face, cylindrical surface, and tooth surface, and a fixed inspection program needs to be edited. Although this method offers high accuracy, the clamping and positioning are complex, the inspection process is cumbersome, and it relies on pre-programming, making it difficult to meet the needs of rapid inspection.

[0005] 2. Manual measurement of the span distance M: Manual measurement using measuring rods and common normal micrometers carries the risk of human error and is inefficient.

[0006] 3. Visual inspection of burrs and defects: The entire process relies on manual visual inspection, which can easily miss tiny burrs or cracks, leading to potential quality problems.

[0007] The drawbacks of these testing technologies are twofold: First, different parameters require switching between specialized equipment (such as coordinate measuring machines, micrometers, etc.), leading to a fragmented testing process and limited efficiency. Second, traditional methods fail to reproduce the true meshing state of the rack and pinion, resulting in discrepancies between the test results and the actual performance after assembly. For example, while coordinate measuring machines can acquire static geometric parameters, they cannot dynamically reflect the comprehensive errors of the rack during meshing motion (such as vibration trajectories). Furthermore, the numerous manual operation steps (such as clamping, visual inspection, and manual measurement) easily introduce subjective errors and are highly dependent on the operator's experience. Utility Model Content

[0008] The purpose of this invention is to provide a rack shaft comprehensive error detection device to achieve rapid and accurate detection of multiple parameters, thereby significantly improving the efficiency and reliability of rack quality control.

[0009] To solve the above-mentioned technical problems, this utility model adopts the following technical solution: a rack shaft comprehensive error detection device, comprising:

[0010] The standard gear is made based on the technical parameters of the mating gear of the rack being tested;

[0011] A drive mechanism is used to drive the standard gear to mesh with the rack under test and perform reciprocating motion.

[0012] The sensor system includes a displacement sensor and an angle sensor, used to detect in real time the displacement and angle changes of the rack under test during reciprocating motion;

[0013] The data processing unit is communicatively connected to the sensor system and is used to convert displacement and angle changes into radial composite error data.

[0014] The display unit is used to output the detection results of the radial synthesis error.

[0015] Preferably, the driving mechanism includes a gear driving mechanism and a rack driving mechanism; the gear driving mechanism includes a first horizontal guide rail and a gear slide plate slidably connected to the first horizontal guide rail, and the standard gear is mounted on the gear slide plate; the rack driving mechanism includes a second horizontal guide rail and a rack slide plate slidably connected to the second horizontal guide rail, and the rack to be tested is mounted on the rack slide plate; the first horizontal guide rail and the second horizontal guide rail are perpendicular to each other, and the gear slide plate can drive the standard gear to move and then contact and mesh with the rack to be tested.

[0016] More preferably, the rack and pinion slide is connected to a motor for driving it to reciprocate along the second horizontal guide rail, the output shaft of the motor is driven by a lead screw, and the bottom end of the rack and pinion slide is fixedly provided with a nut that is driven by the lead screw.

[0017] More preferably, the rack slide plate is provided with a third horizontal guide rail perpendicular to the second horizontal guide rail, and a micro-motion slide plate is slidably connected to the third horizontal guide rail. The rack to be tested is installed on the micro-motion slide plate. A limit groove is provided on one side of the rack slide plate, and a limit block is provided on the corresponding side of the micro-motion slide plate. An elastic component is provided on the rack slide plate for pushing the micro-motion slide plate so that the limit block abuts against the inner wall of the limit groove. A micro-motion grating ruler is installed on the rack slide plate located on the other side of the micro-motion slide plate for recording the vibration trajectory generated during the meshing motion of the rack to be tested with the standard gear.

[0018] More preferably, the displacement sensor includes a first precision grating ruler mounted parallel to one side of the first horizontal guide rail and a second precision grating ruler mounted parallel to one side of the second horizontal guide rail.

[0019] More preferably, a slide block is mounted on the gear slide block, and a base plate is connected to the slide block. The base plate and the slide block are connected by an elastic support or a hinge to allow the base plate to swing slightly under the action of meshing force. The angle sensor includes an angle grating sensor disposed on the slide block. An L-shaped plate is connected to one side of the base plate and the L-shaped plate is located directly below the angle grating sensor. The angle grating sensor calculates the swing angle of the base plate by detecting the displacement of the L-shaped plate.

[0020] Compared with existing technologies, this invention integrates displacement and angle sensors, combined with the reciprocating motion control of the drive mechanism, to achieve multi-parameter synchronous detection of the radial comprehensive error of the rack. This avoids the cumbersome process of switching between multiple devices such as coordinate measuring machines and micrometers required in traditional methods, greatly improving detection efficiency. In this device, the standard gear is customized based on the parameters of the paired gear of the rack under test, and the drive mechanism drives the two to mesh under a set measuring force, completely replicating the actual working state of the gear-rack in the steering gear. This makes the detection results more realistically reflect the torque fluctuation characteristics after rack assembly, and the error detection accuracy can be improved to the micrometer level.

[0021] This invention overcomes the technical bottlenecks of low efficiency, poor accuracy, and high human interference in traditional rack detection by simulating real meshing and using multi-sensor detection, providing a reliable quality control method for the large-scale production of high-precision racks. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure in the embodiment;

[0023] Figure 2 This is a schematic diagram of the front view structure in the embodiment;

[0024] Figure 3 This is a top view of the structure in the embodiment.

[0025] In the picture:

[0026] 1—Standard gear; 2—Rack under test; 3—First horizontal guide rail

[0027] 4 - Gear slide plate 5 - Second horizontal guide rail 6 - Rack and pinion slide plate

[0028] 7 - Motor; 8 - Third horizontal guide rail; 9 - Micro-motion skateboard

[0029] 10 - Limiting groove; 11 - Limiting block; 12 - Elastic component

[0030] 13—Micro-motion grating ruler; 14—First precision grating ruler

[0031] 15—Second Precision Grating Ruler; 16—Slide; 17—Base Plate

[0032] 18—Angle grating sensor; 19—L-shaped plate. Detailed Implementation

[0033] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0034] It should be noted in advance that, in this utility model, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. Furthermore, in this utility model, unless otherwise explicitly specified and limited, "on" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features not in direct contact but through another feature between them.

[0035] like Figures 1 to 3 As shown, a rack shaft comprehensive error detection device includes:

[0036] Standard gear 1, whose tooth profile parameters are based on the technical parameters of the paired gear of the rack 2 under test;

[0037] The drive mechanism is used to drive the standard gear 1 to mesh with the rack 2 under test and perform reciprocating motion.

[0038] The sensor system includes a displacement sensor and an angle sensor, used to detect in real time the displacement and angle changes of the rack 2 under test during reciprocating motion;

[0039] The data processing unit communicates with the sensor system and is used to convert displacement and angular changes into radial composite error data.

[0040] The display unit is used to output the detection results of radial composite error.

[0041] In the above structure, the drive mechanism includes a gear drive mechanism and a rack drive mechanism, specifically:

[0042] The gear drive mechanism includes a first horizontal guide rail 3 and a gear slide plate 4 slidably connected to the first horizontal guide rail 3, with a standard gear 1 mounted on the gear slide plate 4; the rack drive mechanism includes a second horizontal guide rail 5 and a rack slide plate 6 slidably connected to the second horizontal guide rail 5, with the rack 2 to be tested mounted on the rack slide plate 6; the first horizontal guide rail 3 and the second horizontal guide rail 5 are perpendicular to each other, and the gear slide plate 4 can drive the standard gear 1 to move and then contact and mesh with the rack 2 to be tested.

[0043] The rack and pinion slide 6 is connected to a motor 7 for driving it to reciprocate along the second horizontal guide rail 5. The output shaft of the motor 7 is connected to a lead screw, and a nut connected to the lead screw is fixedly installed at the bottom of the rack and pinion slide 6.

[0044] In this embodiment, the rack slide plate 6 is provided with a third horizontal guide rail 8 perpendicular to the second horizontal guide rail 5. A micro-motion slide plate 9 is slidably connected to the third horizontal guide rail 8. The rack 2 to be tested is installed on the micro-motion slide plate 9. A limit groove 10 is provided on one side of the rack slide plate 6, and a limit block 11 is provided on one side of the micro-motion slide plate 9. An elastic component 12 is provided on the rack slide plate 6 to push the micro-motion slide plate 9 so that the limit block 11 abuts against the inner wall of the limit groove 10. A micro-motion grating ruler 13 is installed on the rack slide plate 6 on the other side of the micro-motion slide plate 9 to record the vibration trajectory generated during the meshing motion of the rack 2 to be tested and the standard gear 1. By setting the combined structure of the third horizontal guide rail 8 and the micro-motion slide plate 9, the rack 2 to be tested is allowed to move freely in a direction perpendicular to the main motion direction (the direction of the second horizontal guide rail 5) during meshing, responding in real time to the radial vibration or offset when the standard gear 1 meshes with the rack, ensuring that the sensor system can accurately capture the comprehensive error component of the rack in the direction of small displacement.

[0045] In addition, the displacement sensor includes a first precision grating ruler 14 installed in parallel on one side of the first horizontal guide rail 3 and a second precision grating ruler 15 installed in parallel on one side of the second horizontal guide rail 5. The two grating rulers monitor the X and Y axial displacements respectively.

[0046] For the angle sensor, firstly, a slide block 16 is installed on the gear slide block 4, and a base plate 17 is connected to the slide block 16. The base plate 17 and the slide block 16 are connected by an elastic support or a hinge to allow the base plate 17 to swing slightly under the action of meshing force. The angle sensor includes an angle grating sensor 18 disposed on the slide block 16. An L-shaped plate 19 is connected to one side of the base plate 17 and the L-shaped plate 19 is located directly below the angle grating sensor 18. The angle grating sensor 18 calculates the swing angle of the base plate 17 by detecting the displacement of the L-shaped plate 19.

[0047] In this way, when the rack 2 under test meshes with the standard gear 1 and performs reciprocating motion, if the rack 2 under test has radial composite errors (such as uneven tooth pitch or tooth tilt), the meshing force will force the standard gear 1 to produce dynamic offset, thereby causing the base plate 17 to swing around the support point. The L-shaped plate 19 extending from one side of the base plate 17 serves as an angle amplification mechanism, converting the small swing of the base plate 17 into a significant displacement at the end of the L-shaped plate 19 (lever principle), which is convenient for the angle grating sensor 18 to detect.

[0048] The rack shaft comprehensive error detection device provided in the above embodiment simulates the actual meshing state of the rack and its mating gear using a customized standard gear, driving the rack to reciprocate. Displacement and angle sensors are used to synchronously capture multi-dimensional displacement and angle fluctuation data of the rack during motion in real time. After fusion and analysis by the data processing unit, the dynamic vibration trajectory is converted into radial comprehensive error parameters and visualized. This integrated dynamic meshing detection replaces the traditional multi-device, step-by-step static measurement, achieving efficient and accurate detection of rack radial comprehensive error (micron-level precision), eliminating human error. Simultaneously, through limiting structures, elastic preload, and optimized guide rail references, mechanical interference is effectively suppressed, ensuring that the detection results truly reflect the rack's performance under actual working conditions, significantly improving the efficiency and reliability of production quality control.

[0049] To facilitate understanding by those skilled in the art of the improvements of this utility model compared to the prior art, some of the accompanying drawings and descriptions of this utility model have been simplified. The above embodiments are preferred implementations of this utility model. In addition, this utility model can be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this utility model.

Claims

1. A rack shaft comprehensive error detection device, characterized in that, include: The standard gear (1) is made based on the technical parameters of the paired gear of the rack (2) being tested; The drive mechanism is used to drive the standard gear (1) to mesh with the rack (2) under test and perform reciprocating motion; The sensor system includes a displacement sensor and an angle sensor, used to detect in real time the displacement and angle changes of the rack (2) under test in reciprocating motion; The data processing unit is communicatively connected to the sensor system and is used to convert displacement and angle changes into radial composite error data. The display unit is used to output the detection results of the radial synthesis error.

2. The rack shaft comprehensive error detection device according to claim 1, characterized in that: The drive mechanism includes a gear drive mechanism and a rack drive mechanism; The gear drive mechanism includes a first horizontal guide rail (3) and a gear slide plate (4) slidably connected to the first horizontal guide rail (3), and the standard gear (1) is mounted on the gear slide plate (4). The rack drive mechanism includes a second horizontal guide rail (5) and a rack slide plate (6) slidably connected to the second horizontal guide rail (5), and the rack (2) being tested is mounted on the rack slide plate (6). The first horizontal guide rail (3) and the second horizontal guide rail (5) are perpendicular to each other. The gear slide plate (4) can drive the standard gear (1) to move and then contact and mesh with the rack (2) being tested.

3. The rack shaft comprehensive error detection device according to claim 2, characterized in that: The rack and pinion slide (6) is connected to a motor (7) for driving it to reciprocate along the second horizontal guide rail (5). The output shaft of the motor (7) is connected to a lead screw, and a nut connected to the lead screw is fixedly provided at the bottom end of the rack and pinion slide (6).

4. The rack shaft comprehensive error detection device according to claim 3, characterized in that: The rack and pinion slide (6) is provided with a third horizontal guide rail (8) perpendicular to the second horizontal guide rail (5). A micro-motion slide (9) is slidably connected to the third horizontal guide rail (8). The rack (2) to be tested is installed on the micro-motion slide (9). A limit groove (10) is provided on one side of the rack and pinion slide (6). A limit block (11) is provided on one side of the micro-motion slide (9). An elastic component (12) is provided on the rack and pinion slide (6) to push the micro-motion slide (9) so that the limit block (11) abuts against the inner wall of the limit groove (10). A micro-motion grating ruler (13) is installed on the rack and pinion slide (6) on the other side of the micro-motion slide (9) to record the vibration trajectory generated during the meshing motion of the rack (2) to be tested and the standard gear (1).

5. The rack shaft comprehensive error detection device according to claim 4, characterized in that: The displacement sensor includes a first precision grating ruler (14) installed parallel to one side of the first horizontal guide rail (3) and a second precision grating ruler (15) installed parallel to one side of the second horizontal guide rail (5).

6. The rack shaft comprehensive error detection device according to claim 4, characterized in that: A slide block (16) is mounted on the gear slide block (4), and a base plate (17) is connected to the slide block (16). The base plate (17) and the slide block (16) are connected by an elastic support or a hinge to allow the base plate (17) to swing slightly under the action of meshing force. The angle sensor includes an angle grating sensor (18) set on the slide block (16). An L-shaped plate (19) is connected to one side of the base plate (17) and the L-shaped plate (19) is located directly below the angle grating sensor (18). The angle grating sensor (18) calculates the swing angle of the base plate (17) by detecting the displacement of the L-shaped plate (19).

Images