A process for ensuring side cone angle of gear assemblies

Abstract

The application discloses a kind of process methods for guaranteeing gear assembly side taper angle, it is related to gear transmission technical field, a kind of process methods for guaranteeing gear assembly side taper angle, comprising the following steps: S1: detection conversion, according to the heat after side taper angle required by gear assembly product drawing, gear spiral angle tolerance that the side taper angle is converted into gear detection center detectable by conversion formula, formulate heat before side taper angle conversion table, and design heat before process card according to the conversion table;S2: tooling design, design side taper angle machining fixture, the fixture is adapted gear assembly processing size.The application is by detection conversion, tooling design, machine tool debugging and heat treatment deviation correction mode, the amount of change of gear assembly side taper angle before and after heat treatment is identified and judged, according to actual product demand, the processing technology before heat treatment is adjusted, to ensure that the gear assembly side taper angle after product processing meets the process requirements, further ensure the processing quality of gear assembly.

Description

Technical Field

[0001] This invention relates to the field of gearbox technology, specifically to a process method for ensuring the side cone angle of a gear assembly. Background Technology

[0002] In the machining process of manual transmission gear shaft components, gear shifting requires a synchronizer system. An unqualified side cone angle in the synchronizer system will directly affect the gear shifting performance, resulting in frequent synchronizer disengagement during gear shifting and abnormal wear of the shift fork. Therefore, it needs to be carefully managed. According to feedback from actual production, the side cone angle of the first and second gear assemblies in the existing machining is small (process requirement 3±0.5°). The actual average side cone angle measured after disassembling faulty parts is 2.06°, which is abnormal and needs to be addressed. To this end, we propose a process method to ensure the side cone angle of the gear assembly. Summary of the Invention

[0003] The purpose of this invention is to provide a process method for ensuring the side cone angle of a gear assembly, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a process method for ensuring the side cone angle of a gear assembly, comprising the following steps:

[0005] S1: Inspection conversion. Based on the heat-reduced side cone angle required by the gear assembly product drawing, the side cone angle is converted into the gear helix angle tolerance that can be detected by the gear inspection center through a conversion formula. A heat-prepared side cone angle conversion table is formulated, and a heat-prepared process card is designed based on the conversion table.

[0006] S2: Tooling design, design a side cone angle machining fixture, the fixture is adapted to the machining size of the gear assembly, and avoids interference with the tool during the machining process;

[0007] S3: Machine tool debugging. According to the parameter requirements of the pre-heating process card, adjust the machine tool processing parameters to ensure that the machining accuracy of the pre-heating side cone angle meets the preset range.

[0008] S4: Heat treatment correction, optimizing heat treatment parameters through multiple rounds of testing. The heat treatment parameters include heating temperature, holding time, quenching medium, quenching oil temperature, stirring frequency and quenching time, controlling the side cone angle deformation of the gear assembly during the heat treatment process.

[0009] S5: Process solidification, which interlocks the verified testing conversion standards, fixture parameters, machine tool processing parameters and heat treatment parameters and solidifies them into the processing technology to ensure that the side cone angle of the gear assembly after heat treatment meets the requirements of the product drawing.

[0010] Preferably, the conversion formula in S1 is determined according to the type of the annotation view of the side cone angle. If the annotation view is a normal sectional view of two tooth surfaces, the side cone angle is directly converted with the base circle helix angle.

[0011] If the labeled view is a tangential view, the side cone angle measurement value needs to be divided by the cosine of the pressure angle at the corresponding measurement diameter, and then converted into the base circle helix angle tolerance.

[0012] Preferably, the front side cone angle in S1 is determined based on the target value after heating. If the target side cone angle after heating is 4±0.5°, the front side cone angle is set to 5-5.2°.

[0013] Preferably, the heat treatment parameters in S4 include: heating temperature 840-900℃, holding time 225+t1 min or 250+t1+t2 min (t1 and t2 are the segmented holding times), quenching medium using 355S quenching oil, quenching oil temperature 100℃, quenching oil tank stirring frequency 45HZ, oil draining time 15min, and quenching time 20-600S.

[0014] Preferably, in S4, the side cone angle values ​​before heating, after welding, and after heat treatment are tracked by laser marking to clarify the influence of each process on the side cone angle and optimize the heat treatment parameters accordingly.

[0015] Preferably, the gear assembly is a first or second gear assembly of a manual transmission vehicle, and the side cone angle tolerance after heating is controlled within ±0.5°.

[0016] Preferably, the anti-interference fixture in S2 is made of 45# steel and the surface is hardened. The contact area between the fixture and the gear assembly is provided with a wear-resistant coating to prevent long-term use from causing wear of the fixture and affecting the machining accuracy.

[0017] Preferably, the conversion formula in S1 is as follows: If the labeled view is a normal sectional view, the side cone angle = base circle helix angle + arctan (K) (K is a preset coefficient), and the helix angle tolerance = ±(T / 2) = ±(b×tanβ) (T is the side cone angle tolerance, b is the tooth width, and β is the base circle helix angle); if the labeled view is a tangential view, the side cone angle detection value needs to be divided by the cosine value (cosα_t) of the pressure angle α_t at the corresponding measurement diameter (default pitch circle diameter D), and then converted into the helix angle tolerance according to the normal sectional view conversion logic.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] This invention identifies and judges the change in the side cone angle of the gear assembly before and after heat treatment by means of detection conversion, tooling design, machine tool debugging and heat treatment correction. Based on the actual finished product requirements, the processing technology before heat treatment is adjusted to ensure that the side cone angle of the gear assembly after finished product meets the process requirements, thereby further ensuring the processing quality of the gear assembly. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the process steps of the present invention;

[0021] Figure 2 This is a schematic diagram of the heat treatment time control according to the present invention;

[0022] Figure 3 This is a schematic diagram illustrating the heat treatment quenching time control of the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] Please see Figures 1-3 The illustrated method for ensuring the side cone angle of a gear assembly includes the following steps:

[0026] S1: Inspection conversion. Based on the heat-reduced side cone angle required by the gear assembly product drawing, the side cone angle is converted into the gear helix angle tolerance that can be detected by the gear inspection center through a conversion formula. A heat-prepared side cone angle conversion table is formulated, and a heat-prepared process card is designed based on the conversion table.

[0027] S2: Tooling design, design a side cone angle machining fixture, the fixture is adapted to the machining size of the gear assembly, and avoids interference with the tool during the machining process;

[0028] S3: Machine tool debugging. According to the parameter requirements of the pre-heating process card, adjust the machine tool processing parameters to ensure that the machining accuracy of the pre-heating side cone angle meets the preset range.

[0029] S4: Heat treatment correction, optimizing heat treatment parameters through multiple rounds of testing. The heat treatment parameters include heating temperature, holding time, quenching medium, quenching oil temperature, stirring frequency and quenching time, controlling the side cone angle deformation of the gear assembly during the heat treatment process.

[0030] S5: Process solidification, which interlocks the verified testing conversion standards, fixture parameters, machine tool processing parameters and heat treatment parameters and solidifies them into the processing technology to ensure that the side cone angle of the gear assembly after heat treatment meets the requirements of the product drawing.

[0031] Preferably, the conversion formula in S1 is determined according to the type of the annotation view of the side cone angle. If the annotation view is a normal sectional view of two tooth surfaces, the side cone angle is directly converted with the base circle helix angle.

[0032] If the labeled view is a tangential view, the side cone angle measurement value needs to be divided by the cosine of the pressure angle at the corresponding measurement diameter, and then converted into the base circle helix angle tolerance.

[0033] Preferably, the front side cone angle in S1 is determined based on the target value after heating. If the target side cone angle after heating is 4±0.5°, the front side cone angle is set to 5-5.2°.

[0034] Preferably, the heat treatment parameters in S4 include: heating temperature 840-900℃, holding time 225+t1 min or 250+t1+t2 min (t1 and t2 are the segmented holding times), quenching medium using 355S quenching oil, quenching oil temperature 100℃, quenching oil tank stirring frequency 45HZ, oil draining time 15min, and quenching time 20-600S.

[0035] Preferably, in S4, the side cone angle values ​​before heating, after welding, and after heat treatment are tracked by laser marking to clarify the influence of each process on the side cone angle and optimize the heat treatment parameters accordingly.

[0036] Preferably, the gear assembly is a first or second gear assembly of a manual transmission vehicle, and the side cone angle tolerance after heating is controlled within ±0.5°.

[0037] Preferably, the anti-interference fixture in S2 is made of 45# steel and the surface is hardened. The contact area between the fixture and the gear assembly is provided with a wear-resistant coating to prevent long-term use from causing wear of the fixture and affecting the machining accuracy.

[0038] Preferably, the conversion formula in S1 is as follows: If the labeled view is a normal sectional view, the side cone angle = base circle helix angle + arctan (K) (K is a preset coefficient), and the helix angle tolerance = ±(T / 2) = ±(b×tanβ) (T is the side cone angle tolerance, b is the tooth width, and β is the base circle helix angle); if the labeled view is a tangential view, the side cone angle detection value needs to be divided by the cosine value (cosα_t) of the pressure angle α_t at the corresponding measurement diameter (default pitch circle diameter D), and then converted into the helix angle tolerance according to the normal sectional view conversion logic.

[0039] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process method for ensuring the side cone angle of a gear assembly, characterized in that, Includes the following steps: S1: Inspection Conversion. Based on the heat-reduced side cone angle required by the gear assembly product drawing, the side cone angle is converted into the gear helix angle tolerance that can be detected by the gear inspection center using a conversion formula. A heat-prepared side cone angle conversion table is formulated, and a heat-prepared process card is designed based on the conversion table. S2: Tooling design, design a side cone angle machining fixture, the fixture is adapted to the machining size of the gear assembly, and avoids interference with the tool during the machining process; S3: Machine tool debugging. According to the parameter requirements of the pre-heating process card, adjust the machine tool processing parameters to ensure that the machining accuracy of the pre-heating side cone angle meets the preset range. S4: Heat treatment correction, optimizing heat treatment parameters through multiple rounds of testing. The heat treatment parameters include heating temperature, holding time, quenching medium, quenching oil temperature, stirring frequency and quenching time, controlling the side cone angle deformation of the gear assembly during the heat treatment process. S5: Process solidification, interlocking the verified testing conversion standards, fixture parameters, machine tool processing parameters and heat treatment parameters, and solidifying them into the processing technology to ensure that the side cone angle of the gear assembly after heat treatment meets the requirements of the product drawing; The conversion formula described in S1 is as follows: If the labeled view is a normal sectional view, the side cone angle = base circle helix angle + arctan K, where K is a preset coefficient, and the helix angle tolerance = ±(T / 2) = ±(b×tanβ), where T is the side cone angle tolerance, b is the tooth width, and β is the base circle helix angle; if the labeled view is a tangential view, the side cone angle detection value needs to be divided by the cosine value of the pressure angle α_t at the corresponding measurement pitch circle diameter D, cosα_t, and then converted into the helix angle tolerance according to the normal sectional view conversion logic.

2. The process method for ensuring the side cone angle of a gear assembly according to claim 1, characterized in that: The conversion formula described in S1 is determined based on the type of annotation view for the side cone angle. If the annotation view is a normal sectional view of two tooth surfaces, the side cone angle is directly converted in relation to the base circle helix angle. If the labeled view is a tangential view, the side cone angle measurement value needs to be divided by the cosine of the pressure angle at the corresponding measurement diameter, and then converted into the base circle helix angle tolerance.

3. The process method for ensuring the side cone angle of a gear assembly according to claim 2, characterized in that: The pre-heating side cone angle mentioned in S1 is determined based on the target value after heating. If the target side cone angle after heating is 4±0.5°, the pre-heating side cone angle is set to 5-5.2°.

4. The process method for ensuring the side cone angle of a gear assembly according to claim 3, characterized in that: The heat treatment parameters described in S4 include: heating temperature 840-900℃, holding time 225+t1 min or 250+t1+t2 min, where t1 and t2 are the segmented holding times, quenching medium using 355S quenching oil, quenching oil temperature 100℃, quenching oil tank stirring frequency 45HZ, oil draining time 15min, and quenching time 20-600S.

5. The process method for ensuring the side cone angle of a gear assembly according to claim 1, characterized in that: In S4, laser marking is used to track the side cone angle values ​​before heating, after welding, and after heat treatment to clarify the impact of each process on the side cone angle and optimize the heat treatment parameters accordingly.

6. The process method for ensuring the side cone angle of a gear assembly according to claim 5, characterized in that: The gear assembly is a manual transmission first or second gear assembly for automobiles, and the side cone angle tolerance after heating is controlled within ±0.5°.

7. The process method for ensuring the side cone angle of a gear assembly according to claim 5, characterized in that: The anti-interference fixture described in S2 is made of 45# steel and its surface is hardened. The contact area between the fixture and the gear assembly is coated with a wear-resistant coating to prevent wear of the fixture from affecting the machining accuracy due to long-term use.

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