A multi-datum standard spline gauge and its use method

Abstract

The present invention discloses a multi-datum standard spline gauge, which belongs to the technical field of measuring tools. The present invention discloses a multi-datum standard spline gauge, comprising a core shaft, a standard spline gauge coaxially arranged with the core shaft, a first cylindrical datum axis, a second cylindrical datum axis and a conical datum axis; the core shaft comprises a first center hole and a second center hole coaxially arranged at both ends; the first cylindrical datum axis, the standard spline gauge, the second cylindrical datum axis and the conical datum axis are coaxially arranged in sequence; the pitch error, tooth profile error and tooth direction error of the standard spline gauge itself are all less than 5 microns. The multi-datum standard spline gauge of the present invention has consistent machining and measurement datums, which minimizes the influence of the measurement datum on the tooth thickness measurement and facilitates the evaluation of the measurement accuracy of the tooth thickness parameters.

Description

Technical Field

[0001] The present invention belongs to the technical field of measuring tools, and in particular relates to a multi-reference standard spline gauge. The present invention also relates to a method for using the multi-reference standard spline gauge. Background Art

[0002] Splines are a common connection method in mechanical transmissions, primarily used for circumferential fixation between shafts and components mounted on them to transmit torque. They consist of an external spline on the shaft and an internal spline on the hole. Based on tooth profile, splines can be categorized as involute splines, rectangular splines, and triangular splines. Currently, involute splines are the most widely used, structurally complex, and possess the most parameters.

[0003] Spline (ring, plug) gauges are the primary standard gauges used for comprehensive spline inspection. Spline gauges, which consist of both a go gauge and a stop gauge, are a comprehensive measurement method that can only provide qualitative judgments and cannot accurately measure individual parameters.

[0004] Tooth thickness and space width are the most important parameters for spline gauge reproduction. Currently, direct tooth thickness and space width measurement is difficult to achieve, with limited accuracy and difficulty in standardizing values. There are two common methods for measuring tooth thickness and space width: the measuring rod (or ball) method and the coordinate measurement method.

[0005] According to the GB / T 5106-2006 standard for cylindrical spur involute spline gauges, the tooth thickness and tooth space width are converted into span for judgment. The span of the spline plug gauge can be measured using a length gauge and three needles. This method has the following prominent problems: ① Calculating the upper and lower limits of the span using the tooth thickness tolerance and the theoretical value of the pressure angle can only determine the acceptability of the measured span, and cannot accurately calculate the actual tooth thickness or tooth space width; ② The deviation of the pressure angle is not taken into account; ③ The operation is relatively cumbersome, and it is particularly difficult for splines with odd numbers of teeth because it is difficult to find the optimal position; ④ When measuring splines with odd numbers of teeth, the measurement position does not pass through the spline center, making it difficult to ensure measurement accuracy.

[0006] New coordinate measuring instruments, such as coordinate measuring machines and gear measuring centers, can also measure and calculate tooth thickness when used with their measurement software. However, this method has the following problems: ① Since spline gauges generally use a center hole for positioning, if the center hole and the spline gauge are not aligned, or if the center hole itself is rusted or damaged, using the center hole as a reference will result in significant differences in the tooth thickness at different locations; ② Some instruments can use the tooth pitch itself as a reference for measurement, but if the tooth pitch is poor, the repeatability of the reference cannot be guaranteed, and thus the repeatability of the tooth thickness measurement cannot be guaranteed. Summary of the Invention

[0007] In response to the above-mentioned problems in the prior art, the purpose of the present invention is to provide a clear, easily reproducible and measurable measurement benchmark, and to define tooth thickness parameters for evaluation based on this benchmark, so that the benchmarks and data are consistent when measuring using different measuring equipment and measurement methods.

[0008] The object of the present invention is achieved through the following technical solution: a multi-reference standard spline gauge, comprising a core shaft, a standard spline gauge coaxially arranged with the core shaft, a first cylindrical reference axis, a second cylindrical reference axis and a conical reference axis; the core shaft comprises a first center hole and a second center hole coaxially arranged at both ends;

[0009] The first cylindrical reference axis, the standard spline gauge, the second cylindrical reference axis and the conical reference axis are all coaxially arranged;

[0010] The standard spline gauge has inherent pitch error, tooth profile error, and tooth direction error all less than 5 microns.

[0011] The coaxiality of the first cylindrical reference axis, the second cylindrical reference axis and the line connecting the two top holes is less than or equal to 2 microns.

[0012] The reference cone axis is a cone of any series of Morse or a cone with a taper of 7:24.

[0013] The coaxiality between the cone reference axis and the line connecting the two top holes is less than or equal to 2 microns.

[0014] The coaxiality between the standard spline gauge and the line connecting the two center holes is less than or equal to 2 microns.

[0015] The multi-reference standard spline gauge is integrally formed and has a stable structure.

[0016] The present invention also discloses a method for using a multi-reference standard spline gauge for evaluating the indication error of a tooth thickness instrument. The method uses the standard spline gauge as described above, specifically comprising the following steps:

[0017] a) Preheat according to the instrument instruction manual;

[0018] b) Install the standard spline gauge on the instrument through the locking device so that the standard spline gauge is installed stably and cannot move in the axial direction. Adjust the position and direction of the locking device so that the axis of the standard spline gauge is relatively parallel to one of the measuring axes of the instrument;

[0019] c) In the instrument operation interface, enter the design parameters and evaluation parameters of the standard spline gauge;

[0020] d) First, use the instrument probe system to measure the cylindrical reference axes at both ends of the standard spline gauge to establish a joint axis. This is the reference axis of the standard spline gauge. Use this axis and a cylindrical reference axis to establish the coordinate axis direction and coordinate origin of the coordinate system;

[0021] e) Start the measurement program and follow the program prompts to make the probe contact the specified position of the standard spline gauge, so that the instrument can find the spline gauge to be measured. The program will automatically execute to complete the entire standard spline gauge measurement work;

[0022] f) Compare the measurement results evaluated according to the procedure with the certificate value of the standard spline gauge to determine whether the indication error of the instrument under test meets the requirements.

[0023] Beneficial effects:

[0024] The multi-datum standard spline gauge of the present invention has consistent machining and measurement datums, which minimizes the influence of the measurement datum on tooth thickness measurement and facilitates the evaluation of the measurement accuracy of tooth thickness parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an axial schematic diagram of a multi-reference standard spline gauge of the present invention;

[0026] Figure 2 This is a radial schematic diagram of a multi-reference standard spline gauge of the present invention.

[0027] In the figure: 1-first center hole; 2-second center hole; 3-first concentric cylindrical shaft; 4-second concentric cylindrical shaft; 5-concentric tapered shaft; 6-standard spline gauge; 7-core shaft. DETAILED DESCRIPTION

[0028] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below with reference to the accompanying drawings and examples.

[0029] Example:

[0030] like Figure 1 and Figure 2 As shown, this embodiment discloses a multi-reference standard spline gauge, including a core shaft, a standard spline gauge coaxially arranged with the core shaft, a first cylindrical reference axis, a second cylindrical reference axis and a conical reference axis; the core shaft includes a first center hole and a second center hole coaxially arranged at both ends;

[0031] The first cylindrical reference axis, the standard spline gauge, the second cylindrical reference axis and the tapered reference axis are coaxially arranged in sequence;

[0032] The pitch error, tooth profile error and tooth direction error of the standard spline gauge are all less than 5 microns.

[0033] The coaxiality of the first cylindrical reference axis, the second cylindrical reference axis and the line connecting the two centers is less than or equal to 2 microns.

[0034] The reference cone axis is a Morse cone or a cone with a taper of 7:24. The coaxiality between the cone reference axis and the line connecting the two vertices is less than or equal to 2 microns.

[0035] The coaxiality of the standard spline gauge and the line connecting the two centers is less than or equal to 2 microns.

[0036] The multi-reference standard spline gauge is formed as one piece. If it is a split design, the standard spline gauge must be stable and reliable relative to the core shaft.

[0037] A multi-datum standard spline gauge includes two standard cylindrical surfaces coaxial with the spline parameters, one standard conical surface coaxial with the spline parameters, and two end face top holes as measurement datums: ① During processing, three datum axes coaxial with the spline gauge are clamped and processed at one time to ensure that the coaxiality of the spline parameters and the three datums is within a certain range (generally not exceeding 4μm). ② The shape error and coaxiality of the three two-datum are within a certain range (generally not exceeding 2μm), ensuring that the measurement and evaluation of the datum have minimal impact on the measurement results. ③ Since the length of the datum in the axial direction (generally greater than 100mm) is much larger than the tooth width of the spline gauge (generally less than 20mm), this will greatly reduce the impact of measurement deviation when using the spline gauge tooth pitch itself as a datum. ④ The tooth thickness of the specified tooth is assigned by the spline calibration device. When in use, compare the difference between the instrument under test and the standard value of the spline gauge to determine the accuracy of the tooth thickness measurement of the instrument under test.

[0038] There are two methods to use when measuring:

[0039] (1) When measuring the tooth thickness using a length measuring instrument (such as a length measuring machine, a length gauge, a micrometer, etc.) in conjunction with a measuring needle, the traditional measuring needle method is used to measure the span of the standard spline gauge and calculate the tooth thickness measurement value using a mathematical formula;

[0040] (2) When measuring with a coordinate instrument (coordinate measuring machine, gear measuring center), first connect two cylindrical reference axes to establish a measurement reference, then measure the working surface of the standard spline gauge and evaluate the tooth thickness measurement value of the standard spline gauge.

[0041] There are two methods for use:

[0042] (1) Like traditional spline gauges, it complies with the Taylor principle and is used as a measurement standard to determine whether the spline hole is qualified.

[0043] There are two types of standard spline gauges: full-tooth plug gauge and non-full-tooth plug gauge. The specific usage is as follows:

[0044] 1) Full tooth plug gauge is generally used as a through end plug gauge:

[0045] Used to control the minimum tooth width E of the spline in the workpiece vmin and the minimum diameter of the involute termination circle, which, when used, should completely pass through the entire spline being measured.

[0046] If the integrated through-end plug gauge passes, it means that the total tolerance (T + λ) of the workpiece internal spline meets the limit requirements and satisfies the spline fit. However, the integrated through-end plug gauge cannot determine the conformity of the manufacturing tolerance T and the combined tolerance λ of the workpiece internal spline. Confirmation requires measuring the actual tooth space width (rod spacing) of the workpiece internal spline or performing individual measurements and analysis of the workpiece internal spline's cumulative pitch error, tooth profile error, and tooth guide error.

[0047] If the tooth is stopped by the integrated through-end plug gauge, the plug gauge cannot provide the specific reason for the stop. This also needs to be confirmed by measuring the actual tooth space width (rod spacing) of the spline in the workpiece, or by performing individual measurements and then analyzing and observing the cumulative error of the tooth pitch, tooth shape error, and tooth direction error of the spline in the workpiece.

[0048] 2) Non-full tooth plug gauges are generally used as stop plug gauges:

[0049] Used to control the maximum tooth width E of the spline in the workpiece vmax , it should not enter the spline being tested when in use.

[0050] If the stop gauge is stopped, it means that the total tolerance (T + λ) of the workpiece's internal spline meets the limit requirements. However, the stop gauge cannot determine the conformity of the workpiece's manufacturing tolerance T and the combined tolerance λ individually. Confirmation requires measuring the actual tooth space width (rod spacing) of the workpiece's internal spline, or performing individual measurements and analysis of the workpiece's internal spline's cumulative pitch error, tooth profile error, and tooth guide error.

[0051] If the integrated stop plug gauge passes, it means that the total tolerance (T+λ) of the internal spline of the workpiece exceeds the limit requirement. However, the integrated stop plug gauge cannot determine whether the non-conformity is the manufacturing tolerance T or the integrated tolerance λ of the internal spline of the workpiece. It is also necessary to measure the actual tooth space width (rod spacing) of the internal spline of the workpiece, or to perform individual measurements of the cumulative pitch error, tooth shape error, and tooth direction error of the internal spline of the workpiece and then analyze and observe to confirm.

[0052] (2) Evaluating the indication error of tooth thickness instruments: On the measuring equipment being evaluated, the standard spline can be measured using the top hole, two standard cylindrical datums, and a standard conical datum, depending on the actual situation. Since the three sets of datums are coaxial, the measurement results of different devices are unified. Therefore, by comparing the measurement results with the data measured using the standard spline calibration device to see if they are consistent, it can be determined whether the instrument indication error meets the requirements.

[0053] 1) When evaluating the indication error of tooth thickness measured by a gear measuring center or other measuring equipment with two tips:

[0054] a) Preheat according to the instrument instruction manual;

[0055] b) Install the standard spline gauge between the two centers and lock the centers so that the standard spline gauge is installed stably and cannot move in the axial direction;

[0056] c) In the instrument operation interface, enter the design parameters of the standard spline gauge (number of teeth, module, pressure angle, helix angle, tooth thickness, outer diameter, etc.) and the evaluation parameters (involute evaluation starting position, involute evaluation ending position, helix evaluation starting position, helix evaluation ending position, measuring rod diameter, tooth thickness, tooth space width method, and number of teeth spanned by the normal line length);

[0057] d) Start the measurement program and follow the program prompts to make the probe contact the specified position of the standard spline gauge, so that the instrument can find the spline gauge to be measured. The program will automatically execute to complete the entire standard spline gauge measurement work;

[0058] e) Compare the measurement results evaluated according to the procedure with the certificate value of the standard spline gauge to determine whether the indication error of the instrument under test meets the requirements.

[0059] 2) When evaluating the indication error of tooth thickness measurement using a measuring device without two tips, such as a coordinate measuring machine:

[0060] a) Preheat according to the instrument instruction manual;

[0061] b) Install the standard spline gauge on the instrument using a chuck or other fixture, and lock the fixture so that the standard spline gauge is installed stably and cannot move in the axial direction. Adjust the position and direction of the chuck or other fixture so that the axis of the standard spline gauge is approximately parallel to one of the measuring axes of the instrument;

[0062] c) In the instrument operation interface, enter the design parameters of the standard spline gauge (number of teeth, module, pressure angle, helix angle, tooth thickness, outer diameter, etc.) and the evaluation parameters (involute evaluation starting position, involute evaluation ending position, helix evaluation starting position, helix evaluation ending position, measuring rod diameter, tooth thickness, tooth space width method, and number of teeth spanned by the normal line length);

[0063] d) First, use the instrument probe system to measure the cylindrical reference axes at both ends of the standard spline gauge to establish a joint axis. This axis is the reference axis of the standard spline gauge. Use this axis and a cylindrical reference axis to establish the coordinate axis direction and coordinate origin of the coordinate system.

[0064] e) Start the measurement program and follow the program prompts to make the probe contact the specified position of the standard spline gauge, so that the instrument can find the spline gauge to be measured. The program will automatically execute to complete the entire standard spline gauge measurement work;

[0065] f) Compare the measurement results evaluated according to the procedure with the certificate value of the standard spline gauge to determine whether the indication error of the instrument under test meets the requirements.

[0066] 3) When evaluating the indication error of tooth thickness measurement using a measuring device with a tapered hole:

[0067] b) Pass the standard spline gauge through the tapered mounting hole of the locking device and lock the fixture so that the standard spline gauge is installed stably and cannot move in the axial direction;

[0068] c) In the instrument operation interface, enter the design parameters of the standard spline gauge (number of teeth, module, pressure angle, helix angle, tooth thickness, outer diameter, etc.) and the evaluation parameters (involute evaluation starting position, involute evaluation ending position, helix evaluation starting position, helix evaluation ending position, measuring rod diameter, tooth thickness, tooth space width method, and number of teeth spanned by the normal line length);

[0069] d) First, use the instrument probe system to measure the cylindrical reference axes at both ends of the standard spline gauge to establish a joint axis. This axis is the reference axis of the standard spline gauge. Use this axis and a cylindrical reference axis to establish the coordinate axis direction and coordinate origin of the coordinate system.

[0070] e) Start the measurement program and follow the program prompts to make the probe contact the specified position of the standard spline gauge, so that the instrument can find the spline gauge to be measured. The program will automatically execute to complete the entire standard spline gauge measurement work;

[0071] f) Compare the measurement results evaluated according to the procedure with the certificate value of the standard spline gauge to determine whether the indication error of the instrument under test meets the requirements.

[0072] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application. Other structures and principles are the same as those in the prior art and will not be repeated here.

Claims

1. A multi-reference standard spline gauge, characterized by: It includes a core shaft, a standard spline gauge coaxially arranged with the core shaft, a first cylindrical reference axis, a second cylindrical reference axis and a conical reference axis; the core shaft includes a first top hole and a second top hole coaxially arranged at both ends; The first cylindrical reference axis, the standard spline gauge, the second cylindrical reference axis and the conical reference axis are coaxially arranged in sequence; The standard spline gauge has inherent pitch error, tooth profile error, and tooth direction error all less than 5 microns.

2. The multi-reference standard spline gauge according to claim 1, characterized in that: The coaxiality of the first cylindrical reference axis and the line connecting the first center hole and the second center hole is less than or equal to 2 microns.

3. The multi-reference standard spline gauge according to claim 1, wherein: The coaxiality of the second cylindrical reference axis and the line connecting the first center hole and the second center hole is less than or equal to 2 microns.

4. The multi-reference standard spline gauge according to claim 1, wherein: The conical reference axis is a Morse cone reference axis; or, the taper of the conical reference axis is 7:

24.

5. The multi-reference standard spline gauge according to claim 4, characterized in that: The coaxiality between the cone reference axis and the line connecting the first and second top holes is less than or equal to 2 microns.

6. The multi-reference standard spline gauge according to claim 1, wherein: The coaxiality of the standard spline gauge and the line connecting the first center hole and the second center hole is less than or equal to 2 microns.

7. The multi-reference standard spline gauge according to claim 1, wherein: The multi-reference standard spline gauge is integrally formed.

8. A method for using a multi-reference standard spline gauge for evaluating the indication error of a tooth thickness instrument, using the standard spline gauge according to any one of claims 1 to 7, characterized in that: The specific steps include: a) Preheat according to the instrument instruction manual; b) Install the standard spline gauge on the instrument through the locking device so that the standard spline gauge is installed stably and cannot move in the axial direction. Adjust the position and direction of the locking device so that the axis of the standard spline gauge is relatively parallel to one of the measuring axes of the instrument; c) In the instrument operation interface, enter the design parameters and evaluation parameters of the standard spline gauge; d) First, use the instrument probe system to measure the cylindrical reference axes at both ends of the standard spline gauge to establish a joint axis. This is the reference axis of the standard spline gauge. Use this axis and a cylindrical reference axis to establish the coordinate axis direction and coordinate origin of the coordinate system; e) Start the measurement program and follow the program prompts to make the probe contact the specified position of the standard spline gauge, so that the instrument can find the spline gauge to be measured. The program will automatically execute to complete the entire standard spline gauge measurement work; f) Compare the measurement results evaluated according to the procedure with the certificate value of the standard spline gauge to determine whether the indication error of the instrument under test meets the requirements.

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