Method for designing a spline interference amount

Abstract

The application discloses a spline interference amount design method, and the method comprises the following steps: acquiring spline parameters of a spline; determining a sensor sticking position according to the spline parameters; sticking a stress-strain sensor at the sensor sticking position; performing a press-fitting experiment test on the spline; collecting test stress by using the stress-strain sensor; performing finite element simulation on the spline according to the press-fitting experiment test; obtaining an initial value of the interference amount and simulation stress; and if the difference between the simulation stress and the test stress is less than a first preset threshold, taking the initial value of the interference amount as a design result of the interference amount. The method can realize reasonable design of the interference amount of the spline.

Description

TECHNICAL FIELD

[0001] The present application relates to the spline technology field, and in particular to a spline interference amount design method. BACKGROUND

[0002] In the process of transmitting torque, the continuously changing torque size and direction are realized through the mutual cooperation between the shaft, gear and synchronizer shifting device. In order to reduce the damage to the transmission parts caused by the continuously changing torque, the coupling mode between the synchronizer hub and the shaft adopts spline interference coupling. The spline interference coupling has the advantages of large torque transmission, high automatic centering precision, good performance of bearing variable load impact, high interchangeability, etc. The spline interference coupling is widely used in the fields of automobiles, ships, aviation, aerospace, heavy machinery, etc.

[0003] The reasonable design of the spline interference amount of the synchronizer hub and the shaft determines the precision and service life of the synchronizer. If the interference amount is designed too large, the deformation of the hub and the shaft will be large after assembly, thereby affecting the precision of the synchronizer, and even causing damage to the spline itself and being unable to use. If the interference amount is designed too small, the hub and the shaft are prone to slipping during power transmission, thereby causing wear of the spline and reducing the service life of the synchronizer. However, in the related art, the actual stress of the spline interference amount after assembly cannot be known, so that the spline interference amount cannot be reasonably designed. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the related art. To this end, the present application aims to provide a spline interference amount design method to reasonably design the spline interference amount.

[0005] To achieve the above-mentioned purpose, the present application provides a spline interference amount design method, which comprises: obtaining spline parameters of a spline, determining a sensor sticking position according to the spline parameters; sticking a stress-strain sensor at the sensor sticking position, performing a press fitting experiment test on the spline, and collecting a test stress by using the stress-strain sensor; performing a finite element simulation on the spline according to the press fitting experiment test, obtaining an initial value of the interference amount and a simulation stress, and if the difference between the simulation stress and the test stress is less than a first preset threshold, taking the initial value of the interference amount as a design result of the interference amount.

[0006] The spline interference amount design method of the embodiment of the application, through the spline parameter determination sensor pasting position, pastes the sensor at the position to collect the test stress in the press fitting experiment test process, and obtains the interference amount initial value and the simulation stress according to the press fitting experiment test on the spline for finite element simulation, so as to compare the actual stress with the simulation stress, if the deviation between the actual stress and the simulation stress is within a reasonable range, the interference amount initial value is determined as the final interference amount design result, so that the stress generated by the interference amount can be quantified, which provides a reference basis for the reasonable design of the interference amount, realizes the reasonable design of the spline interference amount, and improves the transmission accuracy and service life of the equipment using the spline such as the synchronizer.

[0007] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a flow chart of the spline interference amount design method of one embodiment of the application;

[0009] Figure 2 is a press fitting experiment test system diagram of one example of the application;

[0010] Figure 3 is a flow chart of the spline interference amount design method of another embodiment of the application;

[0011] Figure 4 is a schematic diagram of the spline interference amount design method of one example of the application;

[0012] Figure 5 is a schematic diagram of the spline interference amount design method of another example of the application. DETAILED DESCRIPTION

[0013] The spline interference amount design method of the embodiment of the application will be described below with reference to the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described with reference to the drawings are exemplary and cannot be understood as limiting the application.

[0014] Figure 1 is a flow chart of the spline interference amount design method of one embodiment of the application.

[0015] As shown in Figure 1 , the spline interference amount design method comprises:

[0016] S11, obtaining the spline parameter of the spline, and determining the sensor pasting position according to the spline parameter.

[0017] S12, paste the stress-strain sensor at the sensor pasting position, and perform a press-fitting experiment test on the spline, and collect a test stress by using the stress-strain sensor.

[0018] S13, perform finite element simulation on the spline according to the press-fitting experiment test, obtain an interference amount initial value and a simulation stress, and if a difference between the simulation stress and the test stress is less than a first preset threshold, take the interference amount initial value as an interference amount design result.

[0019] The first preset threshold has a value range of 8% to 12%, for example, can be 10%, that is, if the error between the measured stress and the simulation stress is within 10%, the interference amount corresponding to the simulation stress can be taken as the interference amount design result, so as to prevent the influence of factors such as measurement error, machining error and visual error on the final obtained interference amount design result. For example, due to the vibration of the mechanical equipment, there is an error between the spline tooth shape and the theoretical tooth shape, and the spline tooth direction and the theoretical tooth direction. Although there is a guide line on the part during the process of pasting the stress-strain sensor, there is still an error in the visual.

[0020] The finite element simulation is a simulation according to the press-fitting experiment test method. The experimental parameters in the press-fitting experiment test can be obtained, and the finite element simulation is performed on the spline according to the experimental parameters. For example, the spline can be the inner and outer splines of a hub and a shaft, and the press-fitting experiment test can be performed by using the device shown in Figure 2 After the positions of the press machine punch, the sleeve, the hub, the shaft and the positioning block are debugged, the press-fitting experiment test can be performed, and the positioning block needs to be kept in a straight line with the press machine punch during the test to avoid inclination and affect the test result. After the press-fitting experiment test is performed, the experimental parameters such as the punch displacement of the press machine punch can be obtained.

[0021] The finite element simulation on the spline can be performed according to the inner and outer spline press-fitting experiment test method, and the simulation stress is obtained. For example, the simulation can be performed according to the device and the specific test method shown in Figure 2 The shaft is fixed, the sleeve top is loaded with axial forced displacement, the punch displacement obtained in the experiment is taken as the displacement input condition, the sleeve and the hub are in frictional contact, and the inner and outer splines are in interference and frictional contact. In this finite element simulation, the value of the friction coefficient can be 0.1, for example.

[0022] Therefore, after the interference amount initial value and the simulation stress are obtained by performing the finite element simulation on the spline, the sensor pasting position is determined according to the spline parameters, the sensor is pasted at the position to collect the test stress in the test process of the press fitting experiment, so as to compare the actual stress with the simulation stress, if the deviation between the actual stress and the simulation stress is within a reasonable range, the interference amount initial value is determined as the final interference amount design result, so that the reasonable design of the spline interference amount is realized.

[0023] In an embodiment of the present application, referring to Figure 3 The sensor pasting position is determined according to the spline parameters, and the sensor is pasted at the position to collect the test stress in the test process of the press fitting experiment.

[0024] S31, the actual interference amount is calculated according to the spline parameters.

[0025] S32, the actual interference amount is decomposed according to the cylindrical coordinate system to obtain the circumferential direction interference amount and the radial direction interference amount.

[0026] S33, the sensor pasting position is determined according to the circumferential direction interference amount and the radial direction interference amount.

[0027] In the specific application process, the specific standard adopted in the spline processing is taken as the basis for design, processing and measurement, and in a specific example of the present application, design, processing and measurement are performed on the basis of the DIN standard. The above-mentioned spline parameters include the base circle radius of the spline and the first pressure angle of the first preset point on the spline. When the spline parameters are detected, DIN5480-2006 can be used. The detection of the spline parameters can be performed in the rectangular coordinate system, and the detection results can be converted to the preset cylindrical coordinate system.

[0028] In order to better describe the technical scheme of the embodiment of the present application, the specific example shown in Figure 4 is described in detail.

[0029] In the specific example, the spline is an inner spline, and the tooth shape of the synchronizer hub and the shaft spline interference joint part is involute. Since the spline of the hub and the shaft is not closed at both ends in the axial direction during the press fitting process, the axial stress can be considered as zero in the direction of the spline tooth shape, and the assembly of the inner and outer splines can be simplified to a two-way stress state for analysis. The coordinate system is converted from the rectangular coordinate system to the cylindrical coordinate system, and the spline interference amount is decomposed.

[0030] Specifically, referring to Figure 4, ef is the right side tooth profile of the inner spline before pressing, ab is the right side tooth profile of the inner spline after pressing, point M is a point on the arbitrary radius circle of ef, that is, the M can be an arbitrary point on ef, and is the above first preset point, point P is the tangent point of the straight line passing through point M and the base circle, M' point is the point of the tooth profile ab after the M point is deformed by extrusion, m is the intersection of OM' and the above arbitrary radius circle, and M" is the intersection of the tooth profile ab and the arbitrary radius circle. PM is the generating line of the involute ef at the M point, and P" M" is the generating line of the involute ab at M". b is the base circle radius, and a1 is the first pressure angle.

[0031] Specifically, in the pressing process, point M is subjected to an extrusion force perpendicular to ef, the pressure direction coincides with the generating line PM, and points P, M and M' are on the same straight line, that is, M' M is the one-side compression amount of the inner spline, and is the actual interference amount, M' M = Δ1.

[0032] The equation of the tooth profile ef can be expressed as:

[0033]

[0034] It can be known that: Figure 4

[0035]

[0036] Therefore:

[0037]

[0038] According to the coordinate transformation rule, the tooth profile ab can be obtained by rotating ef counterclockwise by , and the equation thereof can be expressed as:

[0039]

[0040]

[0041] As shown in Figure 4 , taking M on the original tooth profile ef as the research object, the actual interference amount Δ1 can be decomposed into a radial direction interference amount Δr (that is, the line segment mM') and a circumferential direction interference amount (that is, the circular arc Mm). When the interference amount is known, since the parameters of the tooth profile ef are known conditions, the tooth profile ab is calculated according to the equation of the tooth profile ab, and the circumferential direction interference amount and the radial direction interference amount can be obtained according to the geometric properties of the spline tooth profile involute.

[0042] Among them, the radial direction interference amount after the spline interference assembly is:

[0043] Δr = OM' - OM, ​

[0044] Wherein: α2 is the pressure angle of the point M'; and α1 is the first pressure angle.

[0045] By using the relationship between the angles of the spline tooth profile involute, the relationship between α2 and α1 is derived, that is,

[0046] The radial interference amount equation is converted into an equation containing only the known condition variable α1, that is,

[0047] The circumferential interference amount after the spline interference assembly is:

[0048]

[0049] The circumferential interference amount equation is converted into an equation containing only the known condition variable α1, that is,

[0050]

[0051] Similarly, if the spline is an external spline, the calculation formula is the same as the above internal spline calculation formula, but the direction is opposite.

[0052] After the circumferential interference amount and the radial interference amount are obtained, the sensor pasting position can be determined according to the two interference amounts.

[0053] In an embodiment of the present application, the sensor pasting position is determined according to the circumferential interference amount and the radial interference amount, comprising: obtaining the size relationship between the circumferential interference amount and the radial interference amount; and determining the sensor pasting position according to the size relationship.

[0054] Wherein, the circumferential interference amount is greater than the radial interference amount, that is, the sensitivity in the circumferential direction is higher than that in the radial direction, and it is easier to obtain test data in the test process, so the sensor pasting position is determined to be the position of the stress-strain sensor collecting the circumferential stress.

[0055] In a specific example, since the tooth hub is considered in the design process, the center of the cylindrical surface is concentric with the spline base circle, and the bottom of the claw groove is tangent to the concentric circle of the spline base circle, so the stress-strain sensor can be selected at the bottom of the claw groove, and the direction is tangent to the bottom of the claw groove, for example, for the specific example shown in Figure 4 The circumferential interference amount is greater than the radial interference amount, so the stress-strain sensor is selected at the position corresponding to the tangent point P of the bottom of the claw groove and the above base circle.

[0056] After the sensor pasting position is determined, the stress-strain sensor can be pasted for press fitting test, which is illustrated by the example shown in Figure 5 Figure 5 ​In the middle, AB is the state before pressing, A'B' is the state after pressing, is the stress of the interference in the circumferential direction, σ r is the stress of the interference in the radial direction, σ r +dσ r is the stress in the radial direction after pressing, and let the measured stress displayed by the stress-strain sensor be σ c During the pressing experiment test, the measurement position is pressed in the radial direction and is pulled in the circumferential direction, the circumferential stress is tangent to the measurement point, and there is an angle θ between the circumferential stress and the sensor, at this time the measured stress σ c is related to the circumferential stress Because θ is approximately equal to zero during the test, so

[0057] In summary, the spline interference amount design method of the embodiment of the present application determines the sensor sticking position through the spline parameters, sticks the sensor at the position to collect the test stress in the pressing experiment test, and obtains the interference amount initial value and the simulation stress through the finite element simulation of the spline according to the pressing experiment test, so as to compare the actual stress with the simulation stress, if the deviation between the actual stress and the simulation stress is within a reasonable range, then the interference amount initial value is determined as the final interference amount design result, so that the stress generated by the interference amount can be quantified, which provides a reference basis for the reasonable design of the interference amount, realizes the reasonable design of the spline interference amount, and improves the transmission accuracy and service life of the equipment using the spline such as the synchronizer.

[0058] ​It is to be appreciated that the logical and / or steps represented in the flowcharts, or described herein in other manners, can be considered as a list of ordered steps for implementing logical functions, and can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor- imbedded systems, or other systems that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or in conjunction with such an instruction execution system, apparatus, or device. For purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-readable medium can be a computer- readable storage medium. A specific example (a non-exhaustive list) of computer-readable medium includes the following: an electrical connection having one or more wires, a portable computer diskette, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CD-ROM). Note that the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example via the optical scanner of a device or device, then compiled, interpreted, or processed in a suitable manner, if necessary, and stored in a computer memory.

[0059] It is to be understood that the various parts of the application can be implemented by hardware, software, firmware or a combination thereof. In the foregoing embodiments, a number of steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, and in another embodiment, any of the following technologies, or a combination thereof, can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0060] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in one or more embodiments or examples.

[0061] In the description of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and cannot be understood as a limitation of the present application.

[0062] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0063] In the description of the present application, unless otherwise specified, the terms "mounting", "connecting", "connecting", "fixing" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0064] In the present application, unless otherwise specifically provided and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0065] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as a limitation of the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method of designing a spline interference amount, characterized by, The method comprises: obtaining spline parameters of a spline, determining a sensor sticking position according to the spline parameters; sticking a stress-strain sensor at the sensor sticking position, performing a press fitting experiment test on the spline, and collecting a test stress by using the stress-strain sensor; performing finite element simulation on the spline according to the press fitting experiment test, obtaining an interference amount initial value and a simulation stress, and if a difference between the simulation stress and the test stress is less than a first preset threshold, taking the interference amount initial value as an interference amount design result; the step of determining the sensor sticking position according to the spline parameters comprises: calculating an actual interference amount according to the spline parameters; decomposing the actual interference amount according to a cylindrical coordinate system to obtain a circumferential interference amount and a radial interference amount; determining the sensor sticking position according to the circumferential interference amount and the radial interference amount; the spline parameters comprise a base circle radius of the spline and a first pressure angle of a first preset point on the spline; the circumferential interference amount is obtained according to the following formula: ， wherein is the circumferential direction interference amount, is the base circle radius, is the first pressure angle, is the actual interference amount; the radial interference amount is obtained according to the following formula: ， wherein is the radial interference amount, is the base circle radius, is the first pressure angle, is the actual interference amount.

2. The method of spline interference amount design according to Claim 1, characterized by, the step of determining the sensor sticking position according to the circumferential interference amount and the radial interference amount comprises: obtaining a size relationship between the circumferential interference amount and the radial interference amount; determining the sensor sticking position according to the size relationship.

3. The method of designing a spline interference amount according to claim 2, characterized by, if the circumferential interference amount is greater than the radial interference amount, the sensor sticking position is determined as a position at which the stress-strain sensor collects a circumferential stress.

4. The method of spline interference amount design according to Claim 1, characterized by, the step of performing finite element simulation on the spline according to the press fitting experiment test comprises: obtaining experiment parameters in the press fitting experiment test, and performing the finite element simulation on the spline according to the experiment parameters.

5. The method of designing a spline interference amount according to Claim 1, wherein a value range of the first preset threshold is 8% to 12%.

6. The method of spline interference amount design according to Claim 1, wherein a friction coefficient in the finite element simulation is 0.1.

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