A processing method for the end teeth of a locomotive traction gear shaft

Abstract

The present invention provides a process method for machining the end teeth of a locomotive traction gear shaft, comprising the following steps: designing a fixture, placing the fixture on a machine tool workbench and aligning it; hoisting the active gear workpiece into the fixture and aligning it, and the fixture positioning and clamping the outer circle of the shaft neck on the non-end tooth side of the active gear, using the shaft neck on the non-end tooth side of the active gear as a positioning reference; obtaining the tightening torque of the workpiece for batch production; adjusting the machine tool speed to machine the end teeth of the active gear; after the machining is completed, conducting an online end tooth gauge inspection, unloading the workpiece after the online inspection is qualified, and placing the workpiece on a platform for re-inspection; applying coloring color to the machined end teeth of the active gear and placing it on an end tooth inspection platform for inspection. The present invention realizes that the end tooth milling can be completed by sharing a set of fixtures for multiple vehicle models, saving the auxiliary time of switching fixtures and alignment for small batches of products, and completely changing the positioning method of the end teeth of the active gear milling, and the positioning is more accurate and reasonable.

Description

Technical Field

[0001] The present invention relates to the technical field of gear shaft processing, and more particularly, to a process method for machining the end teeth of a locomotive traction gear shaft. Background Art

[0002] At present, the locomotive traction driving gears of various electric locomotive models are all of the end tooth structure of the gear shaft. The end teeth have high precision. The allowable runout tolerance of the end teeth with respect to the proximal axis of the gear shaft is 0.026 mm, and the allowable runout tolerance with respect to the distal end of the gear shaft is 0.047 mm. As Figure 1 and Figure 3 shown, the machining and detection of the end teeth are difficult.

[0003] The machining of the end teeth needs to be carried out on a high-precision four-axis or five-axis linkage machine tool. The accuracy requirements for the fixture and the tool are high, and the adjustment of the cutting parameters is complex and difficult. After the machining of the end teeth is completed, the end teeth need to be detected. The detection is carried out in two steps. The first step is to use an end tooth gauge on the platform to detect the height to confirm the tooth profile dimensions as Figure 2 shown. The second step is to detect on a special end tooth gauge (end tooth master gauge) to determine the contact area of the end teeth and the runout of the shaft to confirm the form and position tolerance of the end teeth as Figure 3 shown.

[0004] As can be seen from the above, the machining of the driving gear end teeth is a technical difficulty, and a set of applicable end tooth machining process methods need to be developed to achieve the design requirements for the machining of the driving gear end teeth.

[0005] The existing process method for machining the driving gear end teeth is to position with the shaft shoulder end face and the tooth top circle, and clamp the tooth top circle with an expanding mandrel for machining as Figure 4 shown. The fixture is an end tooth fixture produced in Germany purchased. The design and production cycle is long. For the driving gears of different models, different specifications of end tooth fixtures need to be purchased due to different tooth top circle sizes. The fixture is expensive. In addition, for a large batch of driving gears, the wear of the fixture leading to the failure of the fixture is also a big problem. The service life of the fixture is about 5 years. The specific disadvantages are as follows:

[0006] 1) The positioning surface, the tooth top circle (as Figure 1 shown) is not the datum required by the drawing design (the design datum is the shaft necks at both ends of the gear shaft), and there is a systematic error.

[0007] 2) The fixture depends on imported products from Germany, with high purchase cost and long design cycle.

[0008] 3) The tooth top circle diameters of the driving gears of different models are different, so a set of special fixtures need to be configured for each model; too many fixtures not only result in high manufacturing cost, but also high maintenance and storage costs.

[0009] 4) It is impossible to directly detect the height with an end tooth gauge online to confirm the tooth profile, that isFigure 2 It is 312.3 ± 0.1. This dimension is a key dimension for assembly. It can be seen from the existing fixture that it is built inside the fixture. Due to interference from the fixture itself, it cannot be directly measured. Instead, an indirect measurement of 409.4 ± 0.1 is used (as Figure 4 ). There is an error in this indirect measurement method. To ensure the accuracy of the product dimensions, the workpiece can only be removed and re-inspected on the platform. This method may lead to unqualified end tooth milling, and it is impossible to align and restore the position during the second clamping repair, resulting in waste loss.

[0010] 5) When changing the vehicle model during production, the fixture needs to be replaced synchronously. The fixture alignment and adjustment time is long, and the efficiency is low.

[0011] In production and manufacturing, such a process method has high costs, long auxiliary working hours, cannot be directly measured online, and the second clamping cannot guarantee the repeat positioning accuracy, resulting in the production of unqualified products. This process method has high costs and long product switching time. SUMMARY OF THE INVENTION

[0012] In view of the technical problems of the existing process method mentioned above, which has high costs, long auxiliary working hours, cannot be directly measured online, the second clamping cannot guarantee the repeat positioning accuracy, resulting in the production of unqualified products, and long product switching time, a process method for machining the end teeth of a locomotive traction gear shaft is provided. The present invention mainly uses a designed fixture, which can realize the end tooth milling with a set of fixtures for multiple vehicle models, and uses the non-end tooth side journal of the driving gear as the positioning reference to eliminate the system positioning error, suitable for batch production and saving auxiliary working hours.

[0013] The technical means adopted by the present invention are as follows:

[0014] A process method for machining the end teeth of a locomotive traction gear shaft includes the following steps:

[0015] Step 1: Design a fixture, place the fixture on the machine tool workbench and perform alignment;

[0016] Step 2: Lift and place the driving gear workpiece into the fixture and align it. The fixture positions and clamps the outer circle of the non-end tooth side journal of the driving gear, using the non-end tooth side journal of the driving gear as the positioning reference;

[0017] Step 3: Obtain the clamping torque of the workpiece for batch production;

[0018] Step 4: Adjust the machine tool speed to machine the end teeth of the driving gear;

[0019] Step 5: After machining, perform online end tooth gauge inspection. After passing the online inspection, remove the workpiece and place the workpiece on the platform for re-inspection;

[0020] Step 6: Apply coloring agent to the end teeth of the processed driving gear, and then place it on the end tooth detection platform for detection.

[0021] Further, the fixture has a trapezoidal platform structure with a through-hole inside. The shaft section on the non-end tooth side of the driving gear is placed in the through-hole, and an internal expanding mandrel is sleeved outside the shaft section on the non-end tooth side of the driving gear. The internal expanding mandrel is located between the through-hole and the shaft section on the non-end tooth side of the driving gear. The inner wall of the internal expanding mandrel is in close contact with the outer wall of the shaft section on the non-end tooth side of the driving gear, the outer wall of the internal expanding mandrel is in close contact with the inner wall of the through-hole, and the top of the internal expanding mandrel is in contact with the shaft neck on the non-end tooth side of the driving gear. The fixture positions and clamps the shaft neck on the non-end tooth side of the driving gear through the internal expanding mandrel.

[0022] The top of the fixture is provided with a frustum structure. The bottom end of the main scale of the depth caliper is in contact with the upper surface of the frustum, and the cursor is clamped on the upper surface of the end tooth gauge.

[0023] A locking interface is opened on the side wall of the fixture.

[0024] A tensioning device is also arranged in the through-hole. The tensioning device is located below the shaft section on the non-end tooth side of the driving gear and is connected to the internal expanding mandrel. By rotating the locking interface, the tensioning device drives the internal expanding mandrel to move up and down.

[0025] Further, in Step 1, the fixture is aligned through a dial indicator and the runout is ensured to be within 0.005 mm.

[0026] Further, the specific steps of Step 3 are as follows:

[0027] Clamp the driving gear with a torque wrench according to the tested suitable torque, and then use a dial indicator to measure whether the circular runout of the shaft neck on the end tooth side of the driving gear is within 0.005 mm. If so, machining can be carried out; if not, loosen it until the measured circular runout of the shaft neck reaches within 0.005 mm, confirm the clamping torque and record it, which is used as the clamping torque for the workpieces in mass production.

[0028] Further, in Step 4, first perform rough machining on the end teeth of the driving gear, leaving a finishing allowance, ensure that there are no chatter marks on the machined end teeth, the surface roughness meets the designed requirement of Ra3.2, record the machine tool parameters, and then perform finishing until the designed requirements are met.

[0029] Further, in Step 5, perform on-line end tooth gauge detection. The height value measured by the depth caliper is the assembly dimension (which can be 312.3 ± 0.1), and it is qualified if it meets the requirement.

[0030] Further, in Step 5, the re-inspection method is: use the end tooth gauge to detect the height on the platform to confirm the tooth profile dimension.

[0031] Further, in step six, the circular runout of the workpiece, the end-tooth side journal, and the non-end-tooth side journal detected on the special end-tooth gauge of the end-tooth detection platform is less than 0.02 mm, which meets the requirements of the drawing design.

[0032] Further, the special end-tooth gauge is the master end-tooth gauge.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] 1. The process method for machining the end teeth of the locomotive traction gear shaft provided by the present invention determines a new process method for milling the end teeth of the locomotive driving gear.

[0035] 2. The process method for machining the end teeth of the locomotive traction gear shaft provided by the present invention studies and formulates a set of practical process plans for milling the end teeth of the locomotive driving gear, realizes that a set of fixtures can be used for multiple vehicle models to complete end-tooth milling, saves the auxiliary time for small-batch product fixture switching and alignment, and completely changes the positioning method of milling the end teeth of the driving gear, with more accurate and reasonable positioning.

[0036] 3. The process method for machining the end teeth of the locomotive traction gear shaft provided by the present invention has the effects of effective and practical process method, stable and reliable quality, and flexible adjustment plan, and is a very practical end-tooth machining process method.

[0037] 4. The process method for machining the end teeth of the locomotive traction gear shaft provided by the present invention. The application value of the project lies in reducing the tooling purchase cost, adding the function of directly detecting the end-tooth profile dimensions online, avoiding the occurrence of defective products caused by inaccurate tool setting, realizing the flexibility of the end-tooth milling process of the driving gear, and improving the production efficiency.

[0038] 5. The process method for machining the end teeth of the locomotive traction gear shaft provided by the present invention. The development of the project "A process method for machining the end teeth of the locomotive traction gear shaft" further improves the process technology level of manufacturing the end teeth of the locomotive driving gear and constructs a new technical platform for machining the end teeth of the locomotive driving gear.

[0039] In summary, applying the technical solution of the present invention can solve the problems of high process method cost, long auxiliary working hours, inability to directly measure online, inability to guarantee the repeat positioning accuracy due to secondary clamping, resulting in the generation of unqualified products; and long product switching time.

[0040] For the above reasons, the present invention can be widely promoted in the fields such as gear shaft machining. Description of the Drawings

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0042] Figure 1 It is a schematic diagram of the existing driving gear structure.

[0043] Figure 2 It is a schematic diagram for detecting the height with an end tooth gauge on the platform to confirm the tooth profile dimensions.

[0044] Figure 3 It is a schematic diagram for detecting and determining the contact area of the end teeth and the runout of the shaft on a special end tooth gauge (main end tooth gauge) to confirm the end tooth form and position tolerances.

[0045] Figure 4 It is a schematic diagram of the existing original scheme.

[0046] Figure 5 It is a schematic diagram of the solution of the present invention.

[0047] In the figure: 1. End tooth gauge; 2. Depth caliper; 3. Driving gear; 4. Built-in expansion tire; 5. Fixture; 6. Tensioning device; 7. Locking interface. Detailed implementation manners

[0048] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The following will describe the present invention in detail with reference to the drawings and in combination with the embodiments.

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. The description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0050] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0051] Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices should be regarded as part of the authorized specification. In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof is not required in subsequent drawings.

[0052] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal", and "top, bottom", etc. are generally based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present invention: the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0053] For ease of description, spatial relative terms, such as "above", "over", "on the upper surface", "upper", etc., may be used herein to describe the spatial positional relationship of a device or feature shown in the figures with respect to other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, a device described as "above" or "over" other devices or structures will then be positioned "below" or "under" the other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations of the spatial relative descriptions used herein will be made accordingly.

[0054] In addition, it should be noted that the use of terms such as "first", "second", etc. to define components is merely for the convenience of differentiating the corresponding components. Without further statement, the above terms have no special meaning, and thus should not be construed as limiting the scope of protection of the present invention.

[0055] The specific technical solution of the "Process Method for Machining End Teeth of a Locomotive Traction Gear Shaft" of the present invention (for the schematic diagram, see Figure 5 ) is as follows:

[0056] (1) Clamp and position with the outer circle of the non-end tooth side journal of the driving gear, ensuring that the machining positioning reference is consistent with the positioning reference on the design drawing. Clamp and position with the outer circle of the non-end tooth side journal of the driving gear, ensuring that the machining positioning reference is consistent with the positioning reference on the design drawing.

[0057] (2) Design the fixture body with an enlarged upper end face to ensure sufficient space for measuring the height value during the detection of the end tooth gauge, so as to confirm that the tooth profile meets the design requirements and avoid waste loss caused by the inability to repeat positioning during secondary clamping due to the unprocessed qualified dimensions.

[0058] (3) The repeat positioning accuracy requirement of the fixture is 0.005 mm, ensuring that it is not necessary to align each workpiece after clamping during batch production.

[0059] (4) Test and determine a reasonable clamping torque, and design and manufacture a torque wrench interface according to actual requirements.

[0060] (5) Adjust the cutting parameters to ensure the machining accuracy of the end teeth of the driving gear.

[0061] The fundamental guarantee for the development of the "Process Method for Machining End Teeth of a Locomotive Traction Gear Shaft" of the present invention is:

[0062] ① The outer circle of the non-end tooth side journal is determined as the positioning reference to ensure that the machining positioning reference coincides with the design reference and eliminate the systematic positioning error.

[0063] ② Increase the size of the upper end face of the fixture to achieve on-line measurement of the end tooth profile, avoiding the production of unqualified products caused by the inability to perform secondary clamping and machining due to not reaching the design size.

[0064] ③ The repeat positioning accuracy of the fixture reaches 0.005 mm, ensuring accurate positioning in the batch production of the end teeth of the driving gear.

[0065] ④ Adjust the cutting parameters according to the new process method to ensure the dimensional accuracy and roughness requirements of the end tooth machining.

[0066] The purpose of the present invention is to develop and research "a process method for machining the end teeth of a locomotive traction gear shaft", which can solve the following main technical problems:

[0067] (1) Change the positioning method, position and clamp with the outer circle of the journal on the non-end tooth side of the driving gear, ensure consistency with the positioning reference of the design drawing, and eliminate the system positioning error.

[0068] (2) Because the outer circle dimensions of the journals on the non-end tooth sides of the driving gears of current locomotive models are all (as shown in Figure 1 ), and the surface of this journal outer circle is a ground surface with high precision and is also the design reference for the circular runout tolerance of the end teeth (as shown in Figure 3 ), it is more suitable as the positioning reference.

[0069] (3) The design of the fixture body increases the upper end face, which can ensure sufficient space for measuring the height value with a depth caliper during the inspection of the end tooth gauge (as shown in Figure 5 ).

[0070] (4) The fixture has high repeat positioning accuracy, is suitable for batch production, and saves auxiliary working hours.

[0071] (5) Adjust the cutting parameters to avoid cutting chatter marks caused by the cantilever structure and ensure the machining accuracy of the end teeth of the driving gear. Specific embodiments

[0073] The specific implementation of "a process method for machining the end teeth of a locomotive traction gear shaft" is operated according to the following technological process:

[0074] 1) Design a new fixture, place the fixture on the machine tool workbench, and use a dial indicator to align it to ensure that the runout is within 0.005 mm.

[0075] 2) Lift the driving gear workpiece and place it correctly in the fixture. The fixture positions and clamps the outer circle of the journal on the non-end tooth side of the driving gear, using the journal on the non-end tooth side of the driving gear as the positioning reference (measurement reference surface). Clamp it with a torque wrench according to the torque suitable for testing. Then use a dial indicator to measure whether the circular runout of the journal on the end tooth side is within 0.005 mm. If it is, machining can be carried out; otherwise, loosen it until the measured circular runout of the journal reaches within 0.005 mm. Confirm and record the tightening torque, which will be used as the workpiece tightening torque for mass production.

[0076] 3) Adjust the machine tool speed to machine the end teeth of the driving gear. First, perform rough machining, leaving a finishing allowance to ensure that there are no chatter marks on the machined end teeth and the surface roughness meets the design requirement of Ra3.2. Record the machine tool parameters, and then perform finish machining until the design requirements are met.

[0077] 4) After the finish machining is completed, perform on-line end tooth gauge inspection (such as Figure 5 ). If the obtained height value is 312.3 ± 0.1 (the key dimension for assembly) and it is qualified, after the on-line inspection is qualified, the workpiece can be unloaded and placed on a platform for re-inspection (such as Figure 2 ), that is, use an end tooth gauge on the platform to measure the height and confirm the tooth profile dimensions.

[0078] 5) Apply coloring agent to the machined end teeth of the driving gear and place it on the end tooth inspection platform for inspection. According to Figure 3 the requirements, the circular runout of the test sample, the journal on the end tooth side, and the journal on the non-end tooth side should be less than 0.02 mm, meeting the drawing design requirements.

[0079] 6) With this process method, this invention has machined multiple batches of driving gears for different vehicle models, all of which have passed the end tooth gauge inspection and the end tooth inspection platform inspection, meeting the design requirements.

[0080] The fixture 5 designed in the present invention has a trapezoidal table structure and has a through hole inside. The non-end-tooth side shaft section of the driving gear 3 is placed in the through hole. An internal expansion tire 4 is sleeved outside the non-end-tooth side shaft section of the driving gear. The internal expansion tire is located between the through hole and the non-end-tooth side shaft section of the driving gear. The inner wall of the internal expansion tire is in close contact with the outer wall of the non-end-tooth side shaft section of the driving gear, and the outer wall is in close contact with the inner wall of the through hole. The top of the internal expansion tire is in contact with the non-end-tooth side journal of the driving gear. The fixture positions and clamps the non-end-tooth side journal of the driving gear through the internal expansion tire; a frustum structure is provided at the top of the fixture. The top of the inner wall of the frustum structure is in contact with the non-end-tooth side journal of the driving gear. The bottom end of the main scale of the depth gauge 2 is in contact with the upper surface of the frustum. The vernier is stuck on the upper surface of the end-tooth gauge 1. The outer diameter of the frustum structure is larger than the outer diameter of the driving gear; a locking interface 7 is opened on the side wall of the fixture and is used as a torque wrench interface; a tensioning device 6 is further arranged in the through hole, and the tensioning device is located below the non-end-tooth side shaft section of the driving gear. Specifically, during the clamping process of the workpiece, by rotating the locking interface 7, the tensioning device 6 is driven to move up and down. The tensioning device 6 is connected to the internal expansion tire 4, that is, the internal expansion tire 4 is driven to move up and down. The internal expansion tire 4 is a conical structure and forms a fit with the inner hole conical surface of the fixture body. When this conical fit structure has relative displacement, axial force and radial force can be generated. The two forces act on the workpiece simultaneously, making the workpiece reference coincide with the fixture reference. The positioning and clamping accuracy of the workpiece is improved.

[0081] The beneficial effects of the solution of "a process method for machining the end teeth of a locomotive traction gear shaft" applied in the present invention are as follows:

[0082] (1) A new process method for milling the end teeth of a locomotive driving gear is determined.

[0083] (2) This technical solution has developed a set of practical process plans for milling the end teeth of a locomotive driving gear, realizing that a set of fixtures can be shared for multiple vehicle models to complete end tooth milling, saving the auxiliary time for small-batch fixture switching and alignment of products, and completely changing the positioning method of milling the end teeth of the driving gear, with more accurate and reasonable positioning.

[0084] (3) This technical solution has the effects of effective and practical process method, stable and reliable quality, and flexible adjustment plan, and is a very practical end tooth processing process method.

[0085] (4) The application value of the project lies in reducing the tooling purchase cost, adding the function of directly detecting the tooth profile dimensions of the end teeth online, avoiding the occurrence of waste products caused by inaccurate tool setting, realizing the flexibility of the end tooth milling process of the driving gear, and improving the production efficiency.

[0086] (5) The development of the project of "a process method for machining the end teeth of a locomotive traction gear shaft" has further improved the process technology level of manufacturing the end teeth of a locomotive driving gear and constructed a new technical platform for machining the end teeth of a locomotive driving gear.

[0087] The key technical points of the present invention are as follows:

[0088] (1) Change the original positioning method for milling the end teeth of the driving gear, determine a more reasonable positioning surface, so that the machining positioning reference coincides with the design reference, and better ensure the machining dimensional accuracy and geometric tolerance accuracy of the driving gear end teeth.

[0089] (2) The process method is flexible and applicable to all vehicle models, solving the problem of rapid switching in the machining of driving gear end teeth with small batches and multiple varieties, saving the time for fixture switching and fixture alignment, and improving production efficiency.

[0090] (3) Realize on-line direct measurement of tooth profile dimensions, avoid the occurrence of waste products caused by tool setting errors, and the process is more reasonable.

[0091] (4) Reduce the tooling purchase cost.

[0092] The protected points of the present invention:

[0093] (1) Change the original positioning method for milling the end teeth of the driving gear, determine a more reasonable positioning surface, so that the machining positioning reference coincides with the design reference, and better ensure the machining dimensional accuracy and geometric tolerance accuracy of the driving gear end teeth.

[0094] (2) The process method is flexible and applicable to all vehicle models, solving the problem of rapid switching in the machining of driving gears with small batches and multiple varieties, saving the time for fixture switching and fixture alignment, and improving production efficiency.

[0095] (3) Realize on-line direct measurement of tooth profile dimensions, avoid the occurrence of waste products caused by tool setting errors, and the process is more reasonable.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A process method for machining the end teeth of a locomotive traction gear shaft, characterized in that, It includes the following steps: Step 1: Design a fixture, place the fixture on the machine tool workbench and align it; Step 2: Lift and place the driving gear workpiece into the fixture and align it. The fixture positions and clamps the outer circle of the journal on the non-end tooth side of the driving gear, using the journal on the non-end tooth side of the driving gear as the positioning reference; Step 3: Obtain the clamping torque of the workpieces for mass production; Step 4: Adjust the machine tool speed to machine the end teeth of the driving gear; Step 5: After machining, conduct on-line end tooth gauge inspection. After passing the on-line inspection, unload the workpiece and place it on the platform for re-inspection; Step 6: Apply coloring to the machined end teeth of the driving gear and then place it on the end tooth inspection platform for inspection; The fixture has a trapezoidal platform structure and has a through hole inside. The shaft section on the non-end tooth side of the driving gear is placed in the through hole. An internal expansion tire is sleeved outside the shaft section on the non-end tooth side of the driving gear. The internal expansion tire is located between the through hole and the shaft section on the non-end tooth side of the driving gear. The inner wall of the internal expansion tire is in close contact with the outer wall of the shaft section on the non-end tooth side of the driving gear, the outer wall of the internal expansion tire is in close contact with the inner wall of the through hole, and the top of the internal expansion tire is in contact with the journal on the non-end tooth side of the driving gear. The fixture positions and clamps the journal on the non-end tooth side of the driving gear through the internal expansion tire; The top of the fixture is provided with a conical platform structure. The top inner wall of the conical platform structure is in contact with the journal on the non-end tooth side of the driving gear. The bottom end of the main scale of the depth gauge is in contact with the upper surface of the conical platform, and the vernier is stuck on the upper surface of the end tooth gauge; A locking interface is opened on the side wall of the fixture; A tensioning device is also arranged in the through hole. The tensioning device is located below the shaft section on the non-end tooth side of the driving gear and is connected to the internal expansion tire; by rotating the locking interface, the tensioning device drives the internal expansion tire to move up and down.

2. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1, characterized in that, In Step 1, the alignment of the fixture is carried out through a dial indicator and the runout is ensured to be within 0.005 mm.

3. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1, characterized in that, The specific steps of Step 3 are as follows: Clamp the driving gear with a torque wrench according to the tested suitable torque, and then use a dial indicator to measure whether the circular runout of the journal on the end tooth side of the driving gear is within 0.005 mm. If so, machining can be carried out; if not, loosen it until the measured circular runout of the journal reaches within 0.005 mm, confirm the clamping torque and record it, which is used as the clamping torque of the workpieces for mass production.

4. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1, characterized in that, In Step 4, first conduct rough machining on the end teeth of the driving gear, leaving a finishing allowance, ensuring that there are no chatter marks on the machined end teeth, the surface roughness meets the designed Ra3.2 requirement, record the machine tool parameters, and then conduct finish machining until the design requirements are met.

5. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1, characterized in that In Step 5, conduct on-line end tooth gauge inspection. The height value measured by using a depth gauge is the assembly dimension and is considered qualified.

6. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1 or 5, characterized in that, In Step 5, the re-inspection method is: Use an end tooth gauge to inspect the height on the platform to confirm the tooth profile dimension.

7. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 1, characterized in that, In Step 6, on the special end tooth inspection fixture on the end tooth inspection platform, the circular runouts of the workpiece, the journal on the end tooth side, and the journal on the non-end tooth side are all less than 0.02 mm, which meets the drawing design requirements.

8. The process method for machining the end teeth of a locomotive traction gear shaft according to claim 7, characterized in that, The special end tooth inspection fixture is the end tooth master gauge.

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