CN117235938B - Method and system for adjusting contact area of spiral bevel gear - Google Patents
Method and system for adjusting contact area of spiral bevel gear Download PDFInfo
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Abstract
The invention discloses a method and a system for adjusting a contact area of a spiral bevel gear, which relate to the technical field of manufacturing of spiral bevel gears, and the method comprises the following steps: acquiring a tooth surface mismatch amount calculation model; acquiring current parameters of a target adjusting piece; constructing a target tooth surface according to the current mismatch amount and the current tooth surface; adjusting a proportion correction parameter in the tooth surface mismatching calculation model to obtain an updated mismatching amount, and constructing an updated tooth surface according to the updated mismatching amount and the current tooth surface; until the difference between the updated tooth surface and the target tooth surface meets the preset condition, taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as the target proportion correction parameter; constructing target machine tool parameters according to the target proportion correction parameters, the proportion correction adjustment multiplying power and the current machine tool parameters; and processing the target adjusting piece according to the target machine tool parameters to enable the contact area of the target adjusting piece to meet the preset design requirement. The invention can realize more accurate adjustment effect of the helical gear contact area.
Description
Technical Field
The invention relates to the technical field of spiral bevel gear manufacturing, in particular to a method and a device for adjusting a contact area of a spiral bevel gear.
Background
The contact area of the spiral bevel gear is a comprehensive index for measuring the transmission quality of the gear, if the deviation of the size, the shape and the position of the contact area is caused in the processing, manufacturing and assembling, the load is concentrated at the big end or the small end of the tooth, and the load can be also concentrated at the tooth top and the tooth root, so that the edge contact is caused, the local stress concentration is caused, the early abrasion and the tooth breakage of the gear are caused, and the position and the shape of the contact area are directly related to the stability and the noise level of the gear pair during the working.
In order to improve the stability of the gear pair during operation, the adjustment parameters of the machine tool are required to be modified, and the position and the shape of the meshing contact area of the gear pair are changed. In the related art, the normal vector and curvature of a calculation point are corrected by changing the calculation point in the machine tool parameter and the cutter diameter, the proportional relation between the machine tool adjustment parameter and each correction is given, a certain machine tool parameter or the cutter diameter is taken as an independent variable, the change amount of the related machine tool adjustment parameter is calculated through differentiation, and the proportional correction machine tool adjustment parameter corresponding to the adjustment mode item is determined. However, the method adopts increment to replace differential quantity, is a rough empirical adjustment mode, and for the tooth surface after the high-order modification (UMC, diagonal modification), the nonlinear fluctuation of the tooth surface edge tooth shape can be generated by adopting the proportion modification calculation method, so that meshing interference or adjustment failure can be caused.
In the related art, in the manufacturing process of the bevel gear, a machine tool operator modifies the machine tool adjusting parameters according to the rolling result of the contact area of the rolling inspection machine by naked eyes, and changes the position and the shape of the meshing contact area of the gear pair. However, the manual adjustment method depends on operation experience, engagement characteristics are easy to change, adjustment effects are poor, and actual operation is complicated, so that actual application is inconvenient.
Disclosure of Invention
The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the method and the device for adjusting the contact area of the spiral bevel gear, which can realize the more accurate adjustment effect of the parameters of the contact area of the spiral bevel gear.
An adjusting method of a contact area of a spiral bevel gear according to an embodiment of a first aspect of the present invention includes: acquiring a tooth surface mismatch amount calculation model; wherein the tooth surface mismatch calculation model characterizes the relation between the tooth surface mismatch and the proportion correction parameter;
acquiring current parameters of a target adjusting piece; wherein the current parameters include: current mismatch amount, current tooth surface and current machine tool parameters;
constructing a target tooth surface according to the current mismatch amount and the current tooth surface;
the specific steps of adjusting the proportion correction parameters in the tooth surface mismatch calculation model to obtain updated mismatch amount are as follows: if the proportion correction parameter is a correction parameter of the installation dislocation amount, acquiring the current installation dislocation amount, determining a dislocation change amount according to the proportion correction parameter and the current dislocation amount, and adjusting the dislocation change amount in the tooth surface dislocation amount calculation model to obtain the updated dislocation amount;
if the proportion correction parameter is a correction parameter of the tooth surface evaluation value, acquiring a current tooth surface evaluation value, carrying out correction processing on the current tooth surface evaluation value according to the proportion correction parameter to obtain an updated tooth surface evaluation value, and adjusting the updated tooth surface evaluation value in the tooth surface mismatch calculation model to obtain the updated mismatch quantity;
constructing an updated tooth surface according to the updated mismatch amount and the current tooth surface;
taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as a target proportion correction parameter until the difference between the updated tooth surface and the target tooth surface meets a preset condition;
constructing a target machine tool parameter according to the target proportion correction parameter, the proportion correction adjustment multiplying power and the current machine tool parameter;
processing the target adjusting piece according to the target machine tool parameters so that the contact area of the target adjusting piece meets the preset design requirement;
the tooth surface mismatch amount is the geometric correction amount of any designed tooth surface relative to the actual tooth surface, and the proportion correction parameter is the correction parameter of the installation dislocation amount or the tooth surface evaluation value.
According to some embodiments of the invention, the step of setting the ratio correction parameter of the tooth surface mismatch amount calculation model as a target ratio correction parameter until a difference between the updated tooth surface and the target tooth surface satisfies a preset condition includes: acquiring a theoretical coordinate point position on the target tooth surface;
acquiring a corresponding selected coordinate point position on the updated tooth surface according to the theoretical coordinate point position;
constructing residual tooth surface mismatch according to the difference between the theoretical coordinate point position and the selected coordinate point position;
and taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as the target proportion correction parameter until the residual tooth surface mismatch quantity meets a preset condition.
According to some embodiments of the invention, after said constructing a target machine tool parameter from said target proportion correction parameter and said current machine tool parameter, the method further comprises: performing feedback verification on the contact area of the target adjusting piece according to the target machine tool parameters to obtain a feedback verification result;
if the feedback verification result indicates that the contact area does not meet the preset contact requirement, updating the target proportion correction parameter;
and if the feedback verification result indicates that the contact area meets the preset contact requirement, taking the target machine tool parameter as a final machine tool parameter.
According to some embodiments of the present invention, the performing a shape feedback verification on the contact area of the target adjusting piece according to the target machine tool parameter to obtain a feedback verification result includes:
inputting the target machine tool parameters into a preset spiral bevel gear processing model; the spiral bevel gear machining model is used for predicting the influence degree of different machine tool parameters on the tooth profile disturbance;
taking a tooth surface equation as a function taking a machine tool parameter as an independent variable, differentiating an outer layer function of the spiral bevel gear processing model by adopting a composite function derivation principle, differentiating an inner layer function of the spiral bevel gear processing model until the independent variable is solved as the target machine tool parameter, and multiplying differential structures of all layers to obtain the feedback verification result; the feedback verification result is a tooth surface sensitivity factor, and the tooth surface sensitivity factor characterizes disturbance conditions of the target machine tool parameters on tooth shapes.
According to some embodiments of the invention, the machining the target adjusting piece according to the target machine tool parameter so that the contact surface of the target adjusting piece meets a preset design requirement includes:
processing the target adjusting piece according to the target machine tool parameters, and collecting the tooth surface processing condition of the target adjusting piece in real time to obtain tooth surface processing state data;
if the tooth surface machining state data meets the design requirement, continuing to machine the target adjusting piece according to the target machine tool parameters;
and if the tooth surface machining state data does not meet the design requirement, correcting the target proportion adjustment parameter so as to update the target machine tool machining parameter to machine the target adjustment piece.
According to some embodiments of the invention, the tooth surface estimate is one or more of a helix angle estimate, a pressure angle estimate, a tooth length crowning estimate, a tooth profile crowning estimate, and a diagonal error estimate.
According to some embodiments of the invention, the constructing a target machine parameter according to the target proportion correction parameter, the proportion correction adjustment multiplying power and the current machine parameter includes:
when the single-sided method is used for processing, the offset is multiplied by a corresponding proportion correction term to be overlapped so as to determine the proportion correction adjustment multiplying power.
According to some embodiments of the invention, the constructing a target machine parameter according to the target proportion correction parameter, the proportion correction adjustment multiplying power and the current machine parameter includes:
when the double-sided method is used for processing, correction parameters of the driving surface and the non-driving surface are calculated respectively and then overlapped to determine the proportion correction and adjustment multiplying power.
The invention also provides a system for adjusting the parameters of the contact area of the spiral bevel gear, which comprises the following steps: the machine tool is used for machining the bevel gear pair; the rolling inspection machine is used for installing an orthogonal bevel gear pair; and the measuring device is used for measuring the current mismatch quantity of the bevel gear pair, the current tooth surface and the current machine tool parameters. The adjusting device is used for executing the adjusting method of the spiral bevel gear contact area parameters so as to adjust the parameters of the machine tool according to the current mismatch amount, the current tooth surface and the current machine tool parameters.
The method and the device for adjusting the contact area of the spiral bevel gear have the following advantages:
(1) The position of the contact area can be calculated and corrected according to the current mismatch quantity, the current tooth surface and the current machine tool parameters, the correction method is simple, the adjustment of the contact area can not change the meshing characteristics of backlash, jacking clearance and the like, and the consistency of adjustment and design is ensured;
(2) Contact area parameter adjustment based on the misalignment adjustment amount and one or more of a helix angle evaluation value, a pressure angle evaluation value, a tooth length drum evaluation value, a tooth profile drum evaluation value, and a diagonal error evaluation value can be realized;
(3) The method breaks away from a complex bevel gear design link, is suitable for adjusting the contact area of the existing processing adjusting card, and is convenient for use in production;
(4) The adjustment strategy of the position and the shape of any contact area can be realized, and the calculation result is more accurate.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The invention is further described with reference to the accompanying drawings and examples, in which:
FIG. 1 is a flow chart of a proportional correction calculation according to an embodiment of the present invention;
FIG. 2 is a schematic illustration of a bull-gear conjugate tooth surface in accordance with one embodiment of the invention;
FIG. 3 is a schematic illustration of the consistency of tooth surface misalignment, contact area, and evaluation of an embodiment of the present invention;
FIG. 4 is a graph showing the amount of residual tooth surface mismatch based on a target tooth surface in accordance with one embodiment of the present invention;
FIG. 5 is a diagram of a Dog-Leg search algorithm based on a trusted domain according to one embodiment of the present invention;
FIG. 6 is a schematic diagram illustrating the correction verification of the contact area position ratio based on the evaluation value according to one embodiment of the present invention;
FIG. 7 is a schematic diagram illustrating a contact area position ratio correction verification based on misalignment according to an embodiment of the present invention;
FIG. 8 is a schematic diagram illustrating a proportional correction verification based on contact area length in accordance with an embodiment of the present invention;
FIG. 9 is a schematic diagram showing the distribution of the crown of a gear pair before adjustment according to an embodiment of the present invention;
FIG. 10 is a schematic diagram of gear pair backlash distribution prior to adjustment in accordance with an embodiment of the present invention;
FIG. 11 is a schematic diagram of an adjusted gear pair headspace distribution according to one embodiment of the present invention;
fig. 12 is a schematic diagram of an adjusted gear pair backlash distribution according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.
In the description of the present invention, it should be understood that the direction or positional relationship indicated with respect to the description of the orientation, such as up, down, etc., is based on the direction or positional relationship shown in the drawings, is merely for convenience of describing the present invention and simplifying the description, and does not indicate or imply that the apparatus or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.
In the description of the present invention, plural means two or more. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
In the description of the present invention, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present invention can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.
Referring to fig. 1 to 11, a method and an apparatus for adjusting a contact area of a spiral bevel gear according to an embodiment of the present invention include:
acquiring a tooth surface mismatch amount calculation model of the bevel gear pair; wherein, the tooth surface mismatch calculation model characterizes the relation between the tooth surface mismatch and the proportion correction parameter; the bevel gear pair comprises a large gear and a small gear with axes perpendicular to each other, and the installation structure of the large gear and the small gear is shown in fig. 2. The calculation mode of the tooth surface misalignment amount calculation model is to take the large tooth surface in the gear pair as the virtual shovel-shaped tooth surface so as to construct a processing model based on the gear pair misalignment amount, wherein the gear pair misalignment amount comprises the large wheel mounting distance variation amountOffset variation->Small wheel mounting distance variation->Change in the angle of intersection->The method comprises the steps of carrying out a first treatment on the surface of the Wherein the change of the installation distance of the large wheel is->For the displacement of the gearwheel in the direction of its axis, the offset variation is +>For the distance variation between the large gear axis and the small gear axis, the small wheel mounting distance variation +.>For the displacement of the pinion in its axial direction, the amount of change in the angle of intersection +.>Is the amount of angular change between the large gear axis and the small gear axis. Obtaining conjugate tooth surface of large wheel from processing model of gear pair dislocation>，/>The large tooth surface is shown as the tooth surface of the spade wheel.
The tooth surface mismatch is defined as the coincidence of the conjugate tooth surface of the large wheel and the tooth surface of the small wheel at the contact center, and the normal deviation along the tooth surface of the small wheelSince the engagement angle influence is not considered in the contact center neighborhood, it will +.>Differentiating the dislocation amount, and->The approximation is constant, indicating that the effect of the misalignment amount on the tooth surface misalignment amount is linear in the neighborhood of the contact center.
And calculating the tooth surface mismatch amount of all tooth surface discrete points of the meshing area, and obtaining a mismatch chart of the tooth surface mismatch amount of the gear pair. Representing a mismatch map of the tooth surface mismatch amount of the gear pair as a parameter combination according to the characteristics of the space curved surfacePolynomial function of quadratic form ++>I.e.Wherein->The corresponding projection plane coordinates are the evaluation values of the tooth surface mismatch amount, wherein the parameter combination is called the evaluation value of the tooth surface mismatch amount and respectively represents a helix angle factor, a pressure angle factor, a tooth length drum factor, a tooth profile drum factor and a diagonal factor, and the evaluation value of the tooth surface mismatch amount is obtained through fitting calculation by a least square method. As shown in fig. 3, the evaluation values are the tooth surface mismatch amount topological graph and the contact area corresponding to the values in table 1, and the three are in one-to-one correspondence. And correcting the evaluation value to obtain different tooth surface mismatch topological graphs, wherein the different tooth surface mismatch topological graphs are mapped into different contact areas.
TABLE 1
Acquiring current parameters of a target adjusting piece, wherein the target adjusting piece is a bevel gear pair; wherein the current parameters include: current mismatch amount, current tooth surface and current machine tool parameters;
constructing a target tooth surface according to the current mismatch amount and the current tooth surface;
adjusting the proportional correction parameter in the tooth face misalignment amount calculation model to obtain the updated misalignment amount, it is understood that the specific steps of adjusting the proportional correction parameter in the tooth face misalignment amount calculation model to obtain the updated misalignment amount are as follows:
if the proportion correction parameter is a correction parameter of the installation dislocation amount, acquiring the current installation dislocation amount, determining a dislocation change amount according to the proportion correction parameter and the current dislocation amount, and adjusting the dislocation change amount in the tooth surface mismatch amount calculation model to obtain an updated dislocation amount;
and if the proportion correction parameter is a correction parameter of the tooth surface evaluation value, acquiring a current tooth surface evaluation value, carrying out correction processing on the current tooth surface evaluation value according to the proportion correction parameter to acquire an updated tooth surface evaluation value, and adjusting the updated tooth surface evaluation value in the tooth surface mismatch amount calculation model to acquire the updated mismatch amount.
And constructing an updated tooth surface according to the updated mismatch amount and the current tooth surface; wherein the proportion correction parameter is determined by iterative inverse adjustment of the processing parameter with minimized residual tooth surface mismatch amount, and the residual tooth surface mismatch amount isIn the iteration process, the deviation value of the approximated tooth surface corresponding to the solution relative to the target tooth surface along the normal vector direction of the target tooth surface is currently calculated. The method for calculating the mismatching amount of the residual tooth surface comprises the following steps: establishing a residual tooth surface mismatch amount calculation model of the approximated tooth surface and the target tooth surface of the current parameter, wherein the approximation degree takes the residual tooth surface mismatch amount as an evaluation standard; the tooth surface of the theoretical parameter isWherein->Representing an initial set of scale correction machine tool parameters; targeted tooth surface->According to the corresponding theoretical coordinate point->Initial error value of the normal direction +.>The method comprises the following steps: />. Recording the k-th iteration to obtain an approximated tooth surface of +.>At this time, the corresponding machine tool parameter is +.>The condition is satisfied,
wherein set->For the tooth surface parameter solution set corresponding to the discrete point, +.>A set of meshing equation functions representing discrete points; by the process shown in FIG. 4An expression of the residual tooth surface mismatch amount may be determined: />。
The calculation method of the proportion correction parameter comprises the following steps: establishing a general machining parameter inverse adjustment model considering high-order characteristics of an error tooth surface under constraint conditions such as tooth depth, tooth thickness (influencing contact area backlash and head clearance), and the like, and establishing an optimization model based on residual tooth surface mismatch amount, wherein the optimization model is expressed as the following Nonlinear Least Square problem:wherein, the method comprises the steps of, wherein,。
in order to ensure the consistency of the backlash and the head clearance in the engagement process, a constraint function of increasing the tooth depth is needed for a single-sided methodIt is also necessary to increase the constraint function of tooth thickness for the two-sided method>。
Selecting a proportion correction mode item to adjust machine tool parameters, and determining a nonlinear quadratic optimization problem taking the minimization of the residual tooth surface mismatch as an objective function; aiming at the semi-positive characteristic of the objective function, adopting a Dog-Leg algorithm based on a trusted domain to carry out accurate calculation and solution to obtain a stable proportional correction parameter numerical solution; first, the objective functionAt->Performing secondary Taylor expansion to obtain: />Wherein->Corresponding Jacob matrix, +.>，/>，/>Whereby the optimization problem of NLS is converted into the following quadratic form +.>Is not limited to the optimization problem:
wherein->. According to the prior art, the problem can be solved by adopting a Dog-Leg iterative search algorithm based on a trusted domain. Until the difference between the updated tooth surface and the target tooth surface meets the preset condition, taking the proportion correction parameter of the tooth surface mismatch amount calculation model as the target proportion correction parameter, specifically comprising the following steps: an iterative calculation search process as shown in FIG. 5, determines a search path based on Ke Xijie and Newton solutions, and automatically updates the trusted region radius +.>Determining the current iteration solution +.>Substituting the current solution into the objective function, outputting the current solution if the residual error tolerance requirement is met, and otherwise, continuing iteration. Superposing the proportion correction parameters obtained by the Dog-Leg algorithm into the original parameters, carrying out TCA shape feedback verification, and calculating to obtain the physical characteristic change index of the contact area in the adjustment mode; the obtained proportional correction parameters are de-superimposed with a TCA analysis model to determine whether the correction mode is effective, if so, the related physical characteristic change indexes of the contact area, such as the change quantity of the contact center along the tooth length and the tooth profile direction, are further calculated as positionsAnd the reference index of the proportion correction, wherein the length and width change of the contact area and the direction change value of the contact path are used as the reference index of the shape proportion correction. Providing physical characteristic change indexes of the contact area, such as specific position and shape change quantity, and providing theoretical reference for proportional correction and adjustment multiplying power. If TCA shape feedback verification is not satisfied, optimizing the proportion correction parameters to adjust the machine tool parameters, and then continuing to calculate until stable and effective proportion correction parameters are obtained.
Determining a proportion correction adjustment multiplying power according to feedback of a rolling contact area of the rolling inspection machine and a target proportion correction parameter, and then constructing a target machine tool parameter according to the target proportion correction parameter, the proportion correction adjustment multiplying power and the current machine tool parameter; specifically, the tooth surface mismatch amount is multiplied by the ratio correction adjustment magnification and then multiplied by the ratio correction parameter to obtain a machining parameter change amount, and the machining parameter change amount is superimposed on the current machine tool parameter to obtain the target machine tool parameter.
According to the parameters of the target machine tool, the machine tool is adjusted to process the target adjusting piece, so that the contact area of the target adjusting piece meets the preset design requirement; the tooth surface misalignment amount is the geometric correction amount of any designed tooth surface relative to the actual tooth surface, and the proportion correction parameter is the installation misalignment amount or the correction parameter of the tooth surface evaluation value.
Referring to fig. 2 and 3, it can be understood that until the difference between the updated tooth surface and the target tooth surface satisfies the preset condition, taking the proportion correction parameter of the tooth surface mismatch amount calculation model as the target proportion correction parameter includes: acquiring a theoretical coordinate point position on a target tooth surface;
acquiring a corresponding position of a selected coordinate point on the updated tooth surface according to the position of the theoretical coordinate point;
constructing residual tooth surface mismatch amount according to the difference between the theoretical coordinate point position and the selected coordinate point position;
and taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as a target proportion correction parameter until the residual tooth surface mismatch quantity meets a preset condition.
Referring to fig. 3, it will be appreciated that after constructing the target machine parameters from the target proportion correction parameters and the current machine parameters, the method further includes: performing feedback verification on the contact area of the target adjusting piece according to the target machine tool parameters to obtain a feedback verification result;
if the feedback verification result indicates that the contact area does not meet the preset contact requirement, updating the target proportion correction parameter;
and if the feedback verification result shows that the contact area meets the preset contact requirement, taking the target machine tool parameter as the final machine tool parameter.
Referring to fig. 2 and 3, it may be understood that performing a shape feedback verification on a contact area of a target adjustment member according to a target machine tool parameter, to obtain a feedback verification result, including:
inputting target machine tool parameters into a preset spiral bevel gear processing model; the spiral bevel gear machining model is used for predicting the influence degree of different machine tool parameters on the tooth profile disturbance; the calculation method of the spiral bevel gear processing model comprises the following steps: general polynomial coefficients (default 6 th order) of machine tool parameters are recorded asThe corresponding ChebyShev polynomial coefficients areThen +.>Wherein->For the transformation matrix, the polynomial motion form of the machine tool parameters includes the following machining parameter types: roll ratio->Bed->Wheel base mounting angle->Radial cutter positionVertical wheel position->Axial wheel position->Inclination angle of knife->Knife corner->And horizontal distance->Corresponding to the rolling ratio denaturation motion, spiral motion, angular motion, radial motion, vertical motion, axial motion, cutter tilting motion, cutter rotating motion and horizontal motion respectively. For instantaneous cradle angle +.>Machine tool parameter as argument ∈ ->Satisfy->WhereinIs a first class of ChebyShev polynomials; by establishing a mathematical model of bevel gear machining with ChebyShev polynomial type machining parameters, a regularized Jacob matrix is ensured. Then establishing a spiral bevel gear processing mathematical model, discretizing the tooth surface to obtain a radial vector and a normal vector of the ith point>WhereinFor the corresponding tooth flank parameter solution, < >>Corresponding to the tooth surface Gaussian parameter->Corresponding to the generated motion parameter of the tooth surface, +.>Representing the original set of processing parameters. Taking a tooth surface equation as a function taking a machine tool parameter as an independent variable, differentiating an outer layer function of a spiral bevel gear machining model by adopting a composite function derivation principle, differentiating an inner layer function of the spiral bevel gear machining model until the independent variable is solved as a target machine tool parameter, and multiplying differential structures of all layers to obtain a feedback verification result; the feedback verification result is a tooth surface sensitivity factor, and the tooth surface sensitivity factor characterizes disturbance conditions of target machine tool parameters on tooth shapes. Compared with the traditional method that incremental differentiation is directly adopted, the method can avoid the problems of no solution and insufficient calculation precision in solving the nonlinear equation iteration. According to the orthogonality of the ChebyShev polynomial basis, the higher-order coefficients +.>Is nonlinear with respect to each other, and provides a regularized Jacob matrix for subsequent optimization solutions.
Referring to fig. 2, 3 and 7, it can be understood that machining the target adjustment member according to the target machine tool parameter so that the contact surface of the target adjustment member meets the preset design requirement includes:
processing the target adjusting piece according to the target machine tool parameters, and collecting the tooth surface processing condition of the target adjusting piece in real time to obtain tooth surface processing state data;
if the tooth surface machining state data meets the design requirement, continuously machining a target adjusting piece according to the target machine tool parameters;
and if the tooth surface machining state data does not meet the design requirement, correcting the target proportion adjustment parameter so as to update the target machine tool machining parameter to machine the target adjusting piece.
With reference to FIG. 5, it will be appreciated that the parameters are modified based on the target ratioThe target machine tool parameters are constructed by the proportional correction and adjustment multiplying power and the current machine tool parameters, and the method comprises the following steps: when the single-sided method is used for processing, the dislocation quantity on the rolling inspection machine, namely//>And multiplying the value by a corresponding proportion correction term to carry out superposition so as to determine the proportion correction adjustment multiplying power.
Referring to fig. 3 and 4, it can be understood that constructing the target machine parameter according to the target proportion correction parameter, the proportion correction adjustment magnification, and the current machine parameter includes: when the double-sided method is used for processing, correction parameters of the driving surface and the non-driving surface are calculated respectively and then overlapped to determine the proportion correction and adjustment multiplying power. For the double-sided processing, a calculation mode of combining single-sided proportion correction can be adopted, namely one side can be independently adjusted, the other side can not be adjusted, or the two sides can be synchronously and separately adjusted through synchronous adjustment of the two sides, and synchronous adjustment of the two sides can be realized through sharing one set of parameters. By providing physical characteristic change indexes of the contact area, such as specific position and shape change quantity, theoretical reference is provided for the ratio correction and adjustment multiplying power.
Fig. 4 corresponds to the trend of the synchronous contact area change under different evaluation value changes, and according to this principle, the present invention establishes a proportional correction pattern concerning the contact area position and shape of the tooth surface mismatch amount evaluation value and the combination thereof. On the other hand, according to the approximate linear influence mechanism of the dislocation quantity on the tooth surface dislocation quantity topological quantity, the invention establishes a proportion correction adjustment mode based on the dislocation quantity contact zone position.
It is understood that in step S13, the adjustment strategy for the proportional correction selects any one of the adjustment modes based on the misalignment amount and the single adjustment mode based on five evaluation amounts of the helix angle, the pressure angle, the tooth length crowning amount, the tooth profile crowning amount, and the diagonal error, and the adjustment mode based on any combination of the five evaluation amounts.
It can be understood that in step S13, when the adjustment mode based on the offset is selected as the proportion correction adjustment strategy, the calculation method is to determine a certain offset first(e.g) The evaluation value of the lower tooth surface mismatch is +.>Thereby get +.>Increase the amount of change of the tooth surface mismatch amount at 0.1mm +.>. In the standard installation position, the driving surface is calculated +.>The evaluation value of the target tooth surface mismatch amount can be determined asIf the non-driving face is calculated +.>Can determine the target tooth surface mismatch evaluation value asAnd determining the target tooth surface of the adjusted workpiece after equivalent conversion.
The ratio correction adjustment mode is based on the adjustment surface, whether the one-sided method or the two-sided method.
For the adjustment card mode based on five evaluation values or a combination thereof: according to the cooperative change relation between the tooth surface mismatch quantity evaluation value and the contact area, the updated tooth surface mismatch quantity evaluation value is directly taken as the target tooth surface mismatch quantity at the position of the dislocation quantity.
The specific steps for calculating and verifying the proportion correction mode of the pair of the extended epicycloidal rear axle quasi-hyperbolic bevel gear pair by using the adjustment method are as follows:
the tooth blank parameters and machine tool parameters are shown in tables 2 and 3, respectively, and the original contact area, tooth surface misalignment amount, and evaluation value are shown in fig. 5.
TABLE 2
TABLE 3 Table 3
According to the method, according to the correction mode of the evaluation value, the helix angle of the driving surface and the non-driving surface and the evaluation value of the pressure angle are respectively corrected by 15 degrees, and the corresponding position proportion correction and adjustment scheme is obtained as follows:
the small wheel position ratio correction parameter-correction mode based on the evaluation value.
The helix angle +15 degrees, the contact zone was moved away from the small end towards the large end as shown in table 4.
TABLE 4 Table 4
The contact zone was moved away from the root and toward the tip of the tooth by the pressure angle +15 angle, as shown in Table 5.
TABLE 5
As shown in FIG. 6, the contact area distribution of the driving surface helix angle is adjusted to-1 times, the pressure angle is adjusted to 0.5 times, the non-driving surface helix angle is adjusted to 1 time, and the pressure angle is adjusted to-0.5 times. The driving surface tends to be small-end tooth top, and the non-driving surface tends to be large-end tooth root, which is consistent with the design target requirement.
According to the method, the evaluation values of the drive surface and the non-drive surface under the V/H change amount are corrected individually according to the correction pattern of the misalignment amount (V/H value), and the following proportional correction parameters based on the misalignment amount are obtained.
The small wheel position proportion correction parameter-correction mode based on the offset V/H value.
The contact area varies along v+1mm as shown in table 6.
TABLE 6
The contact area varies along h+1mm as shown in table 7.
TABLE 7
As shown in FIG. 7, H+0.06mm for the drive face V+0.05mm on the roller and H-0.03mm for the non-drive face V-0.05 mm. The corresponding multiplying powers, namely the V/H values, are respectively corrected to obtain the corresponding contact area adjustment changes of FIG. 7.
Similarly, according to the method, the ratio correction parameters of the contact area shape can be determined according to the tooth length crowning factor, tooth profile crowning factor and diagonal factor or multi-factor combination mode of the tooth surface mismatch amount respectively corrected according to the correction mode of the evaluation value, the ratio correction parameters of the contact area length are correspondingly shown as follows, and the simulation results of driving surface length adjustment of-0.5 times and non-driving surface length adjustment of 0.5 times are correspondingly shown in fig. 8. Fig. 9 corresponds to a top clearance distribution diagram of the gear pair before adjustment, and fig. 10 corresponds to a side clearance distribution diagram of the gear pair before adjustment. Fig. 11 corresponds to the adjusted crown profile of the gear pair, and fig. 12 corresponds to the adjusted backlash profile of the gear pair. Which is almost identical to the design side and top gaps, it was verified that the engagement characteristics in the contact area adjustment mode are unchanged.
Wheel shape ratio correction parameter-correction pattern based on evaluation value.
The contact area was elongated by 5mm as shown in Table 8.
TABLE 8
The method provided by the invention is suitable for adjusting the contact area of the spiral bevel gear by any processing method such as end face hobbing and end face milling. The method provided by the invention is suitable for the contact area adjustment of spiral bevel gears of any gear type, such as a large gear and a small gear. The method provided by the invention is suitable for adjusting the contact area of the spiral bevel gear in any processing mode, such as a single-sided method and a double-sided method. The method provided by the invention is suitable for adjusting the contact area of the spiral bevel gear with any modified tooth surface, such as diagonal modification, UMC and the like. And the invention constructs two proportion correction adjustment modes.
The embodiment of the invention also provides a system for adjusting the contact area parameters of the spiral bevel gear, which is used for executing the adjustment method of the contact area parameters of the spiral bevel gear, and comprises the following steps:
the machine tool is used for machining the bevel gear pair;
the rolling inspection machine is used for installing an orthogonal bevel gear pair, and the installation mode of the bevel gear pair can be non-orthogonal;
the measuring device is used for measuring the current misalignment amount, the current tooth surface, the misalignment amount and the current machine tool parameters of the bevel gear pair; and the adjusting device is used for executing an adjusting method of the contact area parameters of the spiral bevel gear so as to adjust the parameters of the machine tool according to the current mismatch amount, the current tooth surface and the current machine tool parameters.
The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present invention.
Claims (9)
1. A method of adjusting a contact area of a spiral bevel gear, comprising:
acquiring a tooth surface mismatch amount calculation model; wherein the tooth surface mismatch calculation model characterizes the relation between the tooth surface mismatch and the proportion correction parameter;
acquiring current parameters of a target adjusting piece; wherein the current parameters include: current misalignment amount, current tooth surface, installation misalignment amount, and current machine tool parameters;
constructing a target tooth surface according to the current mismatch amount and the current tooth surface;
the specific steps of adjusting the proportion correction parameters in the tooth surface mismatch calculation model to obtain updated mismatch amount are as follows: if the proportion correction parameter is a correction parameter of the installation dislocation amount, acquiring the current installation dislocation amount, determining dislocation variation according to the proportion correction parameter and the installation dislocation amount, and adjusting dislocation variation in the tooth surface dislocation amount calculation model to obtain the updated dislocation amount;
if the proportion correction parameter is a correction parameter of the tooth surface evaluation value, acquiring a current tooth surface evaluation value, carrying out correction processing on the current tooth surface evaluation value according to the proportion correction parameter to obtain an updated tooth surface evaluation value, and adjusting the updated tooth surface evaluation value in the tooth surface mismatch calculation model to obtain the updated mismatch quantity;
constructing an updated tooth surface according to the updated mismatch amount and the current tooth surface;
taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as a target proportion correction parameter until the difference between the updated tooth surface and the target tooth surface meets a preset condition;
constructing a target machine tool parameter according to the target proportion correction parameter, the proportion correction adjustment multiplying power and the current machine tool parameter;
processing the target adjusting piece according to the target machine tool parameters so that the contact area of the target adjusting piece meets the preset design requirement;
the tooth surface mismatch amount is the geometric correction amount of any designed tooth surface relative to the actual tooth surface, and the proportion correction parameter is the correction parameter of the installation dislocation amount or the tooth surface evaluation value.
2. The method for adjusting the contact area of a spiral bevel gear according to claim 1, wherein: and taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as a target proportion correction parameter until the difference between the updated tooth surface and the target tooth surface meets a preset condition, wherein the method comprises the following steps of: acquiring a theoretical coordinate point position on the target tooth surface;
acquiring a corresponding selected coordinate point position on the updated tooth surface according to the theoretical coordinate point position;
constructing residual tooth surface mismatch according to the difference between the theoretical coordinate point position and the selected coordinate point position;
and taking the proportion correction parameter of the tooth surface mismatch quantity calculation model as the target proportion correction parameter until the residual tooth surface mismatch quantity meets a preset condition.
3. The method for adjusting the contact area of a spiral bevel gear according to claim 2, wherein: after the target machine tool parameters are constructed according to the target proportion correction parameters and the current machine tool parameters, the following steps are carried out: performing feedback verification on the contact area of the target adjusting piece according to the target machine tool parameters to obtain a feedback verification result;
if the feedback verification result indicates that the contact area does not meet the preset contact requirement, updating the target proportion correction parameter;
and if the feedback verification result indicates that the contact area meets the preset contact requirement, taking the target machine tool parameter as a final machine tool parameter.
4. A method of adjusting a contact area of a spiral bevel gear according to claim 3, wherein: performing shape feedback verification on the contact area of the target adjusting piece according to the target machine tool parameters to obtain a feedback verification result, wherein the method comprises the following steps:
inputting the target machine tool parameters into a preset spiral bevel gear processing model; the spiral bevel gear machining model is used for predicting the influence degree of different machine tool parameters on tooth shape, tooth depth and tooth thickness disturbance;
taking a tooth surface equation as a function taking a machine tool parameter as an independent variable, differentiating an outer layer function of the spiral bevel gear processing model by adopting a composite function derivation principle, differentiating an inner layer function of the spiral bevel gear processing model until the independent variable is solved as the target machine tool parameter, and multiplying differential structures of all layers to obtain the feedback verification result; the feedback verification result is a tooth surface sensitivity factor, and the tooth surface sensitivity factor characterizes disturbance conditions of the target machine tool parameters on tooth shape, tooth depth and tooth thickness.
5. The method for adjusting the contact area of a spiral bevel gear according to claim 4, wherein: the processing the target adjusting piece according to the target machine tool parameters so that the contact surface of the target adjusting piece meets the preset design requirement comprises the following steps:
processing the target adjusting piece according to the target machine tool parameters, and collecting the tooth surface processing condition of the target adjusting piece in real time to obtain tooth surface processing state data;
if the tooth surface machining state data meets the design requirement, continuing to machine the target adjusting piece according to the target machine tool parameters;
and if the tooth surface machining state data does not meet the design requirement, correcting the target proportion adjustment parameter so as to update the target machine tool machining parameter to machine the target adjustment piece.
6. The method for adjusting the contact area of a spiral bevel gear according to claim 5, wherein: the tooth surface evaluation value is one or more of a helix angle evaluation value, a pressure angle evaluation value, a tooth length drum shape evaluation value, a tooth profile drum shape evaluation value and a diagonal error evaluation value.
7. The method for adjusting the contact area of a spiral bevel gear according to claim 5, wherein: the step of constructing the target machine tool parameters according to the target proportion correction parameters, the proportion correction adjustment multiplying power and the current machine tool parameters comprises the following steps:
when the single-sided method is used for processing, for a proportion correction adjustment mode based on the dislocation quantity, the dislocation quantity of the rolling inspection machine is the proportion correction adjustment multiplying power, and the dislocation quantity is multiplied by a corresponding proportion correction term to be overlapped so as to determine the target machine tool parameter; for the proportion correction adjustment mode based on the evaluation value, according to the physical characteristic change index of the contact area, the proportion correction adjustment multiplying power is determined in combination with the actual contact area state, and the adjustment multiplying power is multiplied by the corresponding proportion correction term to be overlapped, so that the target machine tool processing parameter is determined.
8. The method for adjusting the contact area of a spiral bevel gear according to claim 7, wherein: the step of constructing the target machine tool parameters according to the target proportion correction parameters, the proportion correction adjustment multiplying power and the current machine tool parameters comprises the following steps:
when the double-sided method is used for processing, correction parameters of a driving surface and a non-driving surface are calculated respectively for a proportional correction adjustment mode based on a dislocation amount or an evaluation value, and then are overlapped to determine a target machine tool processing parameter.
9. An adjustment system for a contact area parameter of a spiral bevel gear, comprising:
the machine tool is used for machining the bevel gear pair;
the rolling inspection machine is used for installing the orthogonal bevel gear pair;
measuring means for measuring the current amount of mismatch of the bevel gear pair, the current tooth surface, and the current machine tool parameter;
adjustment means for performing the adjustment method of the spiral bevel gear contact area parameter of any one of claims 1 to 8 to adjust the parameters of the machine tool according to the current amount of mismatch, the current tooth surface and the current machine tool parameter.
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