A tooth profile involute template for realizing large gear value transmission

Abstract

The present invention belongs to the technical field of gear precision measurement, and specifically relates to a tooth profile involute template for realizing large gear measurement value transmission, including six surfaces, an involute tooth profile cylinder for transmitting parameters, a reference bottom surface and a reference top surface symmetrically arranged on the upper and lower sides, a tooth root reference surface and a tooth top reference surface arranged in parallel on the front and rear sides, and an alignment reference surface relatively arranged on the involute tooth profile cylinder; the distance from the tooth root reference surface to the center of the corresponding base circle is the design distance D. The template proposed by the present invention has more reliable value transmission and can meet the requirements for large gear measurement value traceability; the present invention makes up for the lack of standard measuring instruments in the large diameter involute gear value transmission system, and improves the value traceability system of large gears with a diameter greater than 500mm; the present invention has the advantages of simple structure, simple measurement method and high measurement accuracy, can meet the calibration of high-precision large gear measuring instruments, and is easy to transport, install and adjust, and has good market application prospects and promotion value.

Description

Technical Field

[0001] The invention belongs to the technical field of gear precision measurement, and in particular relates to a tooth profile involute template for realizing large gear value transmission. Background Art

[0002] Large gears are key transmission components of large equipment. With the wide application of large gears in ships, heavy-load helicopters, new energy equipment and other fields and the increasing market demand, the requirements for their performance and quality are getting higher and higher. Large gear measurement is a key link to ensure that gears meet performance requirements and plays a key role in ensuring the normal operation and service life of machinery and equipment.

[0003] High-precision measurement of large gears generally uses off-site measurement (three-coordinate measuring machine and gear measuring center), on-machine measurement and side-mounted measurement. Different measurement methods have different measurement results due to different instrument structures and error sources, and the values ​​cannot be mutually authenticated. In order to achieve the unification of the involute tooth profile value, it is usually necessary to use the involute template as the physical reference of the involute to trace the value of the involute tooth profile deviation, transfer the value and compare the value.

[0004] Generally, the involute template is certified by the National Institute of Metrology and given the corresponding calibration value. The calibrated involute template is then used to calibrate the gear measuring instrument. The gear instrument can measure the gear only after it has been calibrated and corrected by the standard involute template. At the same time, in view of the template specifications for calibrating high-precision gear profile measuring instruments, "ISO 18653:2003" also states that "when calibrating gear measuring equipment, the base circle radius of the involute template used should be greater than 50% of the measuring range of the calibrated instrument". However, the base circle radius of the most commonly used involute template products in industry is less than 200mm. It is not in compliance with the specification to use a template with a small base circle radius to calibrate a large gear measuring instrument.

[0005] Internationally, in 2010, due to the urgent need for wind turbine gear measurement, the German National Metrology Institute (Physikal isch-Technische Bundesanstalt, PTB) developed a 50° sector tooth template with a top circle diameter of 1000mm, a template weight of 450kg, a normal module of 20mm, a pressure angle of 20°, and a tooth width of 400mm. It contains three different types of gear teeth: left-handed 20°, right-handed 10°, and straight teeth. It can be used for tracing involutes and helices, and calibrating gears with a diameter of 1000mm. It needs to be used together with a counterweight during the calibration process used by enterprises.

[0006] In 2018, Germany's PTB released the world's largest involute template in the form of a ring gear. The base circle diameter is about 2000mm and the weight is 2.7 tons. There is only one of them. Because the large gear involute template is too large, it is inconvenient to transport and adjust during use. Its accuracy is easily affected by temperature and support conditions, so it can only be used in a laboratory environment.

[0007] The invention patent (CN 201610847011.2) discloses a large gear involute template composed of an involute template block and a sector-shaped base circle block. It is an involute template for large gears with a base circle radius rb>400mm, including an involute template block, a sector-shaped base circle block, an auxiliary support ball head screw, a positioning pin, and a connecting screw, which are used to calibrate the involute tooth profile deviation measurement accuracy of the gear measuring instrument. However, in principle, this mechanical structure can be separated from the mandrel when in use. As the base circle radius that needs to be transmitted increases, its size also needs to be continuously increased. The use and manufacturing still have the problems of the above solution, so there is only an idea, and no industrial application has been seen in the market.

[0008] In summary, through the analysis of the structure of the existing large base circle radius involute template, it is found that the core geometric elements of the involute template are the involute tooth profile surface and the base circle center. The mechanical structure entity of the template is a structure designed specifically to ensure the relative position between the base circle center and the high-precision involute tooth profile cylindrical surface. The sector-shaped involute template uses the reference hole to represent the base circle center, and the sector-shaped solid part to ensure the precise position of the involute tooth profile surface relative to the base circle center; the ring-shaped template uses the high-precision cylindrical surface to represent the base circle center, and the ring-shaped structure is used to ensure the position of each metering tooth surface relative to the base circle center.

[0009] Constrained by the mechanical structure of the physical sample itself, no matter what form it is, as the value of the base circle radius being transmitted increases, the volume and weight of its physical structure will inevitably increase significantly, which will make it difficult to manufacture the sample, difficult to ensure the stability of accuracy, and difficult to use and compare. Moreover, as a physical benchmark for value comparison, the involute sample with a large base circle radius needs to be frequently transported between various national metrology rooms, laboratories and enterprises. Its huge structure makes it difficult to transport it, and its shape accuracy changes due to the influence of temperature and load. Due to the lack of a large base circle radius involute sample with a light structure, good stability of accuracy and easy to use and compare, the large diameter involute gear tooth profile value transmission system cannot be established, and the measurement results of large gears cannot be traced, which in turn restricts the improvement of the manufacturing level of large gears (diameter greater than 500mm). Summary of the invention

[0010] The present invention aims to provide a tooth profile involute template for realizing large gear measurement transfer, so as to overcome the problems existing in the prior art, such as bulky structure, difficulty in maintaining precision stability, unsuitability for measurement comparison, and inability to establish a large diameter involute gear tooth profile measurement transfer system.

[0011] In order to achieve the purpose of the present invention, the solution of the present invention is: an involute tooth profile template for realizing large gear value transmission, including six surfaces, an involute tooth profile cylinder for transmitting parameters, a reference bottom surface and a reference top surface symmetrically arranged on the upper and lower sides, a root reference surface and a tooth top reference surface parallelly arranged on the front and rear sides, and an alignment reference surface relatively arranged on the involute tooth profile cylinder; the distance from the root reference surface to the center of the corresponding base circle is the design distance D.

[0012] Furthermore, the above-mentioned involute tooth profile cylindrical surfaces include two surfaces that are arranged opposite to each other and have an alignment reference plane as a symmetry plane.

[0013] Furthermore, the base circle radius transmitted by the above template is equivalent to the size of the corresponding standard gear being measured, and the measured length of the template includes the starting point and end point of the corresponding standard gear, which is 1.5 to 2 times the involute length of the corresponding standard gear.

[0014] Furthermore, the thickness of the above-mentioned reference bottom surface and reference top surface is 10 mm to 20 mm, and the tooth surface extends 2 to 3 mm toward the inside of the base circle along the involute tangent at the base circle.

[0015] Furthermore, the spatial positioning of the above-mentioned template is determined by its own reference surface, and the flatness of the reference bottom surface and the reference top surface symmetrically arranged on the upper and lower sides is not greater than 0.5μm, and the surface roughness Ra is not greater than 0.2μm; the root reference surface and the tooth top reference surface arranged in parallel on the front and rear sides are the positioning surfaces of the template, with a flatness of not greater than 0.5μm, a perpendicularity to the reference bottom surface of not greater than 0.5μm, and a surface roughness Ra of not greater than 0.2μm; the shape error of the involute tooth profile cylinder (1) is not greater than 3.0μm, and the surface roughness Ra is not greater than 0.2μm; the flatness of the alignment reference surface (6) is not greater than 0.2μm, the perpendicularity to the reference bottom surface (2) is not greater than 0.4μm, and the surface roughness Ra is not greater than 0.2μm.

[0016] Compared with the prior art, the advantages of the present invention are:

[0017] 1. The present invention proposes an involute template with a large base circle radius, which replaces the design concept of ensuring the relative position of the involute tooth profile and the base circle center by a bulky mechanical structure entity. The size specification of the template is only the size of the gear tooth, and does not increase with the increase of the base circle radius. The transferred value can be determined according to the size of the base circle parameter of the gear being measured, which is conducive to reducing the calibration error and making the value transfer more reliable.

[0018] 2. The base circle radius transmitted by the large base circle radius tooth profile involute template proposed by the present invention can exceed the specification of the maximum base circle diameter of the existing gear template of 2000mm. At the same time, because of its small structural size and low manufacturing difficulty, its manufacturing accuracy is comparable to that of small and medium-sized involute templates, which can meet the traceability requirements of large gear measurement values.

[0019] 3. The sample proposed in the present invention has a small size and is therefore insensitive to temperature changes, which facilitates value comparison between metrology rooms, laboratories and enterprises in various countries. The shape accuracy of the sample is not affected by the environment, temperature and load during transportation, and its own accuracy is highly stable, which is beneficial to reducing the uncertainty of value transfer.

[0020] 4. The tooth profile involute template proposed in the present invention makes up for the lack of standard measuring instruments in the measurement transmission system of large-diameter involute gears, and improves the measurement traceability system of large gears with a diameter greater than 500 mm.

[0021] 5. The present invention has the advantages of simple structure, simple measuring method and high measuring accuracy, can meet the calibration of high-precision large gear measuring instruments, and is easy to transport, install and adjust, and has good market application prospects and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the overall structure diagram of the sample of Example 1;

[0023] Figure 2 yes Figure 1 The opposite structure diagram;

[0024] Figure 3 is a schematic diagram of the template positioning reference surface of Example 1;

[0025] Figure 4 It is the overall structure diagram of the sample of Example 2;

[0026] Figure 5 yes Figure 4 The opposite structure diagram;

[0027] Figure 6 It is a schematic diagram of the template positioning reference plane of Example 2.

[0028] The reference numerals are as follows:

[0029] 1-involute tooth profile cylinder; 2-reference bottom surface; 3-reference top surface; 4-tooth root reference surface; 5-tooth top reference surface; 6-alignment reference surface; 7-reference surface where the tooth root reference surface is located; 8-reference surface where the reference bottom surface is located; 9-reference surface where the alignment reference surface is located. DETAILED DESCRIPTION

[0030] The method of the present invention is described in detail below with reference to the accompanying drawings.

[0031] Example 1, see Figure 1 , Figure 2 : A tooth profile involute template with a large base circle radius, comprising an involute cylinder 1 for transmitting parameters, a reference bottom surface 2 and a reference top surface 3 symmetrically arranged on the upper and lower sides, a tooth root reference surface 4 and a tooth top reference surface 5 arranged in parallel on the front and rear sides, and an alignment reference surface 6 arranged relative to the involute tooth profile cylinder 1. The involute shape of the tooth profile template depends on the size of the base circle, so the tooth profile involute template provided by the present invention introduces the parameter of the base circle center position as the characteristic parameter of the template, that is, the distance from the tooth root reference surface 4 of the template to the corresponding base circle center is used as the design distance D to characterize this parameter.

[0032] See also Figure 3 Based on the structure, the present invention provides three mutually perpendicular reference planes, namely, a reference plane 7 where the tooth root reference plane is located, a reference plane 8 where the reference bottom plane is located, and a reference plane 9 where the alignment reference plane is located.

[0033] Example 2, see Figure 4 , Figure 5 : A tooth profile involute template with a large base circle radius, with the alignment reference plane 6 as the symmetry plane, the template of this embodiment includes two involute tooth profile cylinders 1 arranged opposite to each other, with reference bottom surfaces 2 and reference top surfaces 3 symmetrically arranged on the upper and lower sides, and tooth root reference surfaces 4 and tooth top reference surfaces 5 arranged in parallel on the front and rear sides. The involute shape of the tooth profile template depends on the size of the base circle, so the tooth profile involute template provided by the present invention introduces the parameters of the base circle center position as the characteristic parameters of the template, that is, the distance from the tooth root reference surface 4 of the template to the corresponding base circle center is used as the design distance D to characterize this parameter.

[0034] See also Figure 6 Based on the structure, the present invention provides three mutually perpendicular reference planes, namely, a reference plane 7 where the tooth root reference plane is located, a reference plane 8 where the reference bottom plane is located, and a reference plane 9 where the alignment reference plane is located.

[0035] In the embodiments 1 and 2, the base circle radius transmitted by the template is equivalent to the size of the corresponding standard gear being measured, and the measured length of the template includes the starting point and end point of the corresponding standard gear, which is 1.5 to 2 times the involute length of the corresponding standard gear.

[0036] The thickness of the reference bottom surface 2 and the reference top surface 3 of the template is 10mm~20mm, and the tooth surface extends 2~3mm inside the base circle along the involute tangent at the base circle to prevent the loss of involute expansion length caused by chamfering or machining collapse at the root of the involute template.

[0037] The spatial positioning of the template is determined by its own reference surface. The flatness of the reference bottom surface 2 and the reference top surface 3 symmetrically arranged on the upper and lower sides is not greater than 0.5μm, and the surface roughness Ra is not greater than 0.2μm; the tooth root reference surface 4 and the tooth top reference surface 5 arranged parallel to the front and rear sides are the positioning surfaces of the template, with a flatness of not greater than 0.5μm, a perpendicularity to the reference bottom surface 2 of not greater than 0.5μm, and a surface roughness Ra of not greater than 0.2μm. The shape error of the involute tooth profile cylinder (1) is not greater than 3.0μm, and the surface roughness Ra is not greater than 0.2μm; the flatness of the alignment reference surface (6) is not greater than 0.2μm, the perpendicularity to the reference bottom surface (2) is not greater than 0.4μm, and the surface roughness Ra is not greater than 0.2μm.

[0038] According to different measuring instruments, the large gear measurement methods mainly include the generating method, the polar coordinate method and the rectangular coordinate system method. The following is divided into two cases to describe the specific use method of the tooth profile involute template provided by the present invention for realizing large gear value transmission:

[0039] 1) When the development method and polar coordinate method are used for measurement, the present invention provides three mutually perpendicular reference planes 7 where the tooth root reference planes are located, reference plane 8 where the reference bottom plane is located, and reference plane 9 where the alignment reference plane is located, which are parallel to the coordinate system established with the origin of the rotation center of the measurement system. The center position of the base circle corresponding to the template is adjusted to coincide with the origin of the rotation center of the measurement system, and the distance from the tooth root reference plane 4 to the rotation center of the measurement system is ensured to be the designed distance D, and the correct position of the template is completed. After the position of the template is determined, the template rotates with the workbench, and the probe of the large gear measuring instrument follows to measure the tooth profile deviation of the involute tooth profile. The performance of the tooth surface deviation measurement of the tooth profile deviation evaluation instrument is used to achieve the traceability of the base circle radius.

[0040] 2) When the rectangular coordinate method is used for measurement, the reference plane 7 where the three mutually perpendicular root reference planes of the template are located, the reference plane 8 where the reference bottom surface is located, and the reference plane 9 where the alignment reference surface is located are provided by the present invention and are parallel to the coordinate system established with the measurement system as the origin of the center of rotation. The center position of the base circle corresponding to the template is adjusted to coincide with the origin of the center of rotation of the measurement system, and the distance from the root reference plane 4 to the center of rotation of the measurement system is ensured to be the designed distance D, and the correct position of the template is completed. After the position is determined, the template does not move, and only the probe of the large gear measuring instrument moves to measure the tooth profile deviation of the involute tooth profile at any position. After completing the measurement of the first position, the rotary table drives the template to rotate to any angle and measure again. Repeat the steps, and measure at least two positions to comprehensively evaluate the performance of the instrument's tooth profile deviation measurement and achieve traceability of the base circle radius.

[0041] Before use, in a constant temperature environment of 20±1℃, use special equipment to precisely measure the tooth profile involute sample and determine the base circle radius r of the tooth profile involute sample. b0 , accurate to 0.1μm; if the involute profile inclination deviation of the tooth profile involute template is not zero during the measurement process, it can be compensated to the base circle radius r b0 and the compensated r b As the base circle information parameter of the large gear involute template, that is, the calibration value of the template.

[0042] The above description is only the technical method and implementation mode of the present invention, and the protection scope of the present invention is not limited thereto. Any person who makes equivalent replacement or change based on the technical solution and inventive concept of the present invention is covered by the protection scope of the present invention.

Claims

1. A method for using a tooth profile involute template for realizing large gear measurement value transfer, wherein the tooth profile involute template for large gear measurement value transfer has the following structure: comprising six surfaces, an involute tooth profile cylindrical surface (1) for transmitting parameters, a reference bottom surface (2) and a reference top surface (3) symmetrically arranged on the upper and lower sides, a tooth root reference surface (4) and a tooth top reference surface (5) arranged in parallel on the front and rear sides, and an alignment reference surface (6) arranged opposite to the involute tooth profile cylindrical surface (1), wherein the distance from the tooth root reference surface (4) to the center of the corresponding base circle is a design distance D, and characterized in that: According to different measuring instruments, the large gear measurement methods include the development method, polar coordinate method and rectangular coordinate system method. When the development method and polar coordinate method are used for measurement, the reference surface (7) where the three mutually perpendicular tooth root reference surfaces are located, the reference surface (8) where the reference bottom surface is located, and the reference surface (9) where the alignment reference surface are located are provided to be parallel to the coordinate system established with the rotation center origin of the measurement system; the base circle center position corresponding to the template is adjusted to coincide with the rotation center origin of the measurement system, and the distance from the tooth root reference surface (4) to the rotation center of the measurement system is ensured to be the design distance D, and the correct position of the template is completed; after the position of the template is determined, the template rotates with the workbench, and the probe of the large gear measuring instrument follows, and the tooth profile deviation of the involute tooth profile is measured. The performance of the tooth surface deviation measurement of the instrument is evaluated through the tooth profile deviation, and the traceability of the base circle radius is realized; When measuring by the rectangular coordinate method, the three mutually perpendicular reference surfaces (7) of the template, the reference surface (8) of the reference bottom surface and the reference surface (9) of the alignment reference surface are provided to be parallel to the coordinate system established with the rotation center origin of the measurement system; the base circle center position corresponding to the template is adjusted to coincide with the rotation center origin of the measurement system, and the distance from the root reference surface (4) to the rotation center of the measurement system is ensured to be the design distance D, and the correct position of the template is completed; after the position is determined, the template does not move, and only the probe of the large gear measuring instrument moves, and the tooth profile deviation of the involute tooth profile is measured at any position; after completing the measurement of the first position, the rotary table drives the template to rotate to any angle and measure again; repeat the steps, and at least through the measurement of two positions, the performance of the instrument tooth profile deviation measurement can be evaluated by comprehensive measurement results, and the traceability of the base circle radius can be achieved.

2. The method for using the tooth profile involute template for realizing large gear value transfer according to claim 1, characterized in that: The involute tooth profile cylindrical surface (1) comprises two surfaces which are arranged opposite to each other and which have an alignment reference surface (6) as a symmetry surface.

3. The method for using a tooth profile involute template for realizing large gear value transfer according to claim 1 or 2, characterized in that: The base circle radius transmitted by the template is equivalent to the size of the corresponding standard gear being measured. The measured length of the template includes the starting point and end point of the corresponding standard gear, which is 1.5 to 2 times the involute length of the corresponding standard gear.

4. The method for using the tooth profile involute template for realizing large gear value transfer according to claim 3 is characterized in that: The thickness of the reference bottom surface (2) and the reference top surface (3) is 10 mm to 20 mm, and the tooth surface extends 2 to 3 mm toward the inside of the base circle along the involute tangent at the base circle.

5. The method for using the tooth profile involute template for realizing large gear value transfer according to claim 4 is characterized in that: The spatial positioning of the template is determined by its own reference surface. The flatness of the reference bottom surface (2) and the reference top surface (3) symmetrically arranged on the upper and lower sides is not greater than 0.5μm, and the surface roughness Ra is not greater than 0.2μm; the tooth root reference surface (4) and the tooth top reference surface (5) arranged in parallel on the front and rear sides are the positioning surfaces of the template, with a flatness of not greater than 0.5μm, a perpendicularity to the reference bottom surface (2) of not greater than 0.5μm, and a surface roughness Ra of not greater than 0.2μm; the shape error of the involute tooth profile cylinder (1) is not greater than 3.0μm, and the surface roughness Ra is not greater than 0.2μm; the flatness of the alignment reference surface (6) is not greater than 0.2μm, the perpendicularity to the reference bottom surface (2) is not greater than 0.4μm, and the surface roughness Ra is not greater than 0.2μm.

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