A method for eliminating Fourier paradoxes

Abstract

This invention discloses a method for eliminating Fourier strange orders, comprising the following steps: Step 1: Grinding vibration is generated during gear grinding, and the grinding tool speed and Z-axis feed per revolution in the finishing stage affect the vibration. The strange order is eliminated by disrupting the grinding vibration and thus disrupting the resulting order error. Step 2: Adjust the grinding speed from 4425 rpm to 4625 rpm, process the part, and generate a Fourier report showing the presence of order 113 in the tooth direction. Step 3: Adjust the grinding speed from 4625 rpm to 4825 rpm, process the part, and generate a Fourier report showing the presence of order 113 in the tooth direction. This invention eliminates the strange order by disrupting the grinding vibration and thus disrupting the resulting order error, effectively reducing the NVH-dB value deviation problem of the entire vehicle; and improving the problem of noise transmission to the cab, which interferes with the driver and affects safety.

Description

Technical Field

[0001] The present invention relates to the technical field of gear processing, and particularly to a method for eliminating Fourier ghost orders. Background Art

[0002] The principle of Fourier transform is a mathematical tool that can transform a signal from the time domain to the frequency domain, thereby realizing signal analysis and processing. The application of Fourier transform is very extensive. In audio processing, Fourier transform can decompose an audio signal into sound waves of different frequencies, thereby realizing audio spectrum analysis and filtering. For example, in the process of gear transmission, it can collect the meshing vibration waves of a pair of mating gears, and finally output an order error report by analyzing the tooth surface ripple to evaluate whether the gear Fourier is qualified.

[0003] The transmissions of existing hybrid or electric vehicles operate very quietly. Therefore, even a tooth surface error of 0.5 microns will cause gear noise problems. Such specific tooth surface errors are called ripples caused by the tooth surface hard machining process (such as gear grinding) on the tooth surface. When the gear rotates, ripples will continuously appear in the radial direction of the involute tooth profile and the direction perpendicular to the tooth surface. Therefore, a 0.5-micron error does not only occur on one tooth, but on all teeth. The gear error is called a ghost order error. The ghost order error has nothing to do with the natural order caused by the number of gear teeth Z and is usually caused by extremely small errors (less than 0.002 mm) in the gear grinding process. To solve the problem of vehicle noise, we propose a method for eliminating Fourier ghost orders. Summary of the Invention

[0004] The purpose of this part is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this part, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this part, the abstract, and the title, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0005] In view of the problems existing in the above-mentioned existing methods for eliminating Fourier ghost orders, the present invention is proposed.

[0006] Therefore, the purpose of the present invention is to provide a method for eliminating Fourier ghost orders, which eliminates the ghost order by disrupting the grinding vibration and thus disrupting the generated order error, effectively reducing the problem of vehicle NVH-dB value exceeding the standard; and improving the problem that noise is transmitted to the cab, interfering with the driver and affecting safety.

[0007] To solve the above technical problems, the present invention provides the following technical solution: A method for eliminating Fourier ghost orders, comprising the following steps:

[0008] Step 1: Grinding vibration will be generated during the gear grinding process. The grinding tool speed and the Z-axis feed per revolution in the fine grinding stage will affect the vibration. The order error generated by the grinding vibration is eliminated by disrupting the grinding vibration.

[0009] Step 2: Adjust the grinding speed: change it from 4425 rpm to 4625 rpm, process the part and generate a Fourier report, showing that tooth direction 113 exists;

[0010] Step 3: Adjust the grinding speed: change it from 4625rpm to 4825rpm, process the part and generate a Fourier report, showing that tooth direction 113 exists;

[0011] Step 4: Adjust the Z-axis feed per revolution during the fine grinding stage from 0.25mm to 0.2mm, machine the part and generate a Fourier report, showing that tooth order 113 exists;

[0012] Step 5: Adjust the Z-axis feed per revolution during the fine grinding stage from 0.2mm to 0.152mm, process the part and generate a Fourier report, showing that the tooth direction 113th order has been eliminated.

[0013] In a preferred embodiment of the method for eliminating Fourier strange order described in this invention, the processed part is selected as the input shaft of a reducer.

[0014] As a preferred embodiment of the method for eliminating Fourier strange order described in this invention, in steps two and three, only the grinding speed is adjusted, and the Z-axis feed per revolution in the fine grinding stage is 0.25 mm.

[0015] As a preferred embodiment of the method for eliminating Fourier strange order described in this invention, in steps four and five, only the Z-axis feed per revolution is adjusted during the fine grinding stage, and the grinding speed is 4425 rpm.

[0016] As a preferred embodiment of the method for eliminating Fourier paradoxical order described in this invention, in step four, the Z-axis feed is 0.2 mm: order / Z, which corresponds to 113 / 0.2 = 565, a multiple relationship; in step five, the Z-axis feed is 0.152 mm: order / Z, which corresponds to 113 / 0.152 = 743.4210526, a non-multiple relationship, and in the tooth direction, the paradoxical order 113 is eliminated.

[0017] As a preferred embodiment of the method for eliminating Fourier strange order described in this invention, wherein: the part before processing in step five is installed in the vehicle and passes the noise test: 113th order, dB value 160, which is unqualified; the part after processing in step five is installed in the vehicle and passes the noise test: 113th order, dB value 142, which is qualified.

[0018] The beneficial effects of this invention are as follows: This invention eliminates the order error generated by disrupting grinding vibration, thereby effectively reducing the problem of excessive NVH-db values ​​in the whole vehicle; and improves the problem of noise transmission to the cab, which interferes with the driver and affects safety. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0020] Figure 1 This is a schematic diagram illustrating the method steps of the present invention for eliminating Fourier paradoxes.

[0021] Figure 2 This is a schematic diagram of the Fourier report for the grinding speed of 4625 rpm in the method for eliminating Fourier strange steps according to the present invention.

[0022] Figure 3 This is a schematic diagram of the Fourier report for a grinding speed of 4825 rpm in the method for eliminating Fourier strange steps according to the present invention.

[0023] Figure 4 This is a schematic diagram of the Fourier report for the method of eliminating Fourier paradoxes of the present invention, with a Z-axis feed of 0.2 mm per revolution.

[0024] Figure 5 This is a schematic diagram of the Fourier report for the method of eliminating Fourier paradoxes of the present invention, with a Z-axis feed of 0.152 mm per revolution.

[0025] Figure 6 The NVH curves are for the method of eliminating Fourier strange order of the present invention. Detailed Implementation

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0027] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0028] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0029] Secondly, the present invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.

[0030] Reference Figures 1-6 A method for eliminating Fourier paradoxes is provided, comprising the following steps:

[0031] Step 1: Grinding vibration will be generated during the gear grinding process. The grinding tool speed and the Z-axis feed per revolution in the fine grinding stage will affect the vibration. The order error generated by the grinding vibration is eliminated by disrupting the grinding vibration.

[0032] Step 2: Adjust the grinding speed: change it from 4425 rpm to 4625 rpm, refer to... Figure 2 The machined parts and generated a Fourier transform report, showing the existence of tooth direction 113;

[0033] Step 3: Adjust the grinding speed: change it from 4625 rpm to 4825 rpm, refer to... Figure 3 The machined parts and generated a Fourier transform report, showing the existence of tooth direction 113;

[0034] Step 4: Adjust the Z-axis feed per revolution during the finishing grinding stage from 0.25mm to 0.2mm, referring to... Figure 4 The machined parts and generated a Fourier transform report, showing the existence of tooth direction 113;

[0035] Step 5: Adjust the Z-axis feed per revolution during the finishing grinding stage from 0.2mm to 0.152mm, referring to... Figure 5 The machined parts and generated a Fourier report showed that the tooth direction was eliminated at order 113.

[0036] The input shaft of the reducer is used to process the parts.

[0037] In steps two and three, only the grinding speed is adjusted, and the Z-axis feed per revolution is 0.25mm in the fine grinding stage; in steps four and five, only the Z-axis feed per revolution is adjusted in the fine grinding stage, and the grinding speed is 4425rpm.

[0038] Furthermore, in step four, the Z-axis feed is 0.2mm: order / Z, which corresponds to 113 / 0.2 = 565, a multiple relationship; in step five, the Z-axis feed is 0.152mm: order / Z, which corresponds to 113 / 0.152 = 743.4210526, a non-multiple relationship. In the tooth direction, the 113th order is eliminated.

[0039] The fifth step, before further processing, involves assembling the pre-processed parts into the vehicle and passing a noise test: 113th order, dB value 160, which fails the test; refer to... Figure 6 After processing in step five, the parts were installed in the vehicle and passed the noise test: level 113, dB value of 142, which is qualified.

[0040] This invention eliminates the order error caused by disrupting grinding vibration, thereby effectively reducing the problem of excessive NVH-dB values ​​in the whole vehicle; and improves the problem of noise transmission to the cab, which interferes with the driver and affects safety.

[0041] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for eliminating Fourier paradoxical orders, characterized in that, Includes the following steps: Step 1: Grinding vibration will be generated during the gear grinding process. The grinding tool speed and the Z-axis feed per revolution in the fine grinding stage will affect the vibration. The order error generated by the grinding vibration is eliminated by disrupting the grinding vibration. Step 2: Adjust the grinding speed: change it from 4425 rpm to 4625 rpm, process the part and generate a Fourier report, showing that tooth direction 113 exists; Step 3: Adjust the grinding speed: change it from 4625rpm to 4825rpm, process the part and generate a Fourier report, showing that tooth direction 113 exists; Step 4: Adjust the Z-axis feed per revolution during the fine grinding stage from 0.25mm to 0.2mm, machine the part and generate a Fourier report, showing that tooth order 113 exists; Step 5: Adjust the Z-axis feed per revolution during the fine grinding stage from 0.2mm to 0.152mm, machine the part and generate a Fourier report, showing that the tooth direction 113th order has been eliminated; In step four, the Z-axis feed is 0.2mm: order / Z, which corresponds to 113 / 0.2=565, a multiple relationship; in step five, the Z-axis feed is 0.152mm: order / Z, which corresponds to 113 / 0.152=743.4210526, a non-multiple relationship. In the tooth direction, the 113th order is eliminated.

2. The method for eliminating Fourier paradoxes according to claim 1, characterized in that: The part to be machined is selected from the input shaft of a speed reducer.

3. The method for eliminating Fourier paradoxes according to claim 2, characterized in that: In steps two and three, only the grinding speed is adjusted, and the Z-axis feed per revolution is 0.25 mm during the fine grinding stage.

4. The method for eliminating Fourier paradoxes according to claim 3, characterized in that: In steps four and five, only the Z-axis feed per revolution is adjusted during the fine grinding stage, and the grinding speed is 4425 rpm.

5. The method for eliminating Fourier paradoxes according to claim 1, characterized in that: The parts processed in step five, before being installed in the vehicle, passed the noise test: 113th order, dB value 160, which is unqualified; the parts processed in step five, after being installed in the vehicle, passed the noise test: 113th order, dB value 142, which is qualified.

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