Spline angular self-positioning spline molded surface rounding machining method

Abstract

The invention discloses a spline angular self-positioning spline molded surface rounding processing method which comprises the following steps: S1, arranging a key slot on a slotting cutter, designing a matched key on a slotting cutter bar, and enabling the angular relationship of the slotting cutter relative to a machine tool to be consistent, wherein the angular relationship between the key slot and any tooth of the slotting cutter is consistent; designing a clamp with a positioning pin to fix the part on a numerical control machining center; s2, at least one positioning hole is machined in the part; s3, a forming column milling cutter matched with the spline molded surface in rounding size is adopted for rounding the spline molded surface; according to the invention, the tool cost is saved, and the time for aligning the angular position of the spline before rounding the molded surface of the spline is greatly shortened.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, in particular to a method for processing a spline profile rounding with spline angular self-positioning. Background Art

[0002] Spline connection is a common mechanical connection method. In the design of splines, rounding the spline surface can effectively reduce stress concentration and improve the fatigue strength and fracture resistance of parts. On the other hand, the rounding of the spline surface increases the storage space of the spline lubricant, making it easier for the lubricant to enter the spline contact surface to form a uniform oil film, reducing the friction and wear of the spline. In addition, the rounding of the spline surface can effectively prevent the sharp edges and corners of the spline from being damaged and scratched during the operation of the spline.

[0003] At present, the CNC chamfering process of spline surface has gradually begun to be studied, but one of the key difficulties is to align the angular direction of the spline before processing. The conventional solution is to design some auxiliary tooling or fixtures to complete the angular positioning of the spline, which greatly increases the tooling cost and time cost of spline chamfering.

[0004] The patent with publication number CN106735602A discloses a gear shaping tooling and processing method for internal spline parts of aviation with small module, including a clamping body, a blocking body, a hexagon socket cylindrical head screw, a positioning plate, a positioning spindle, a spline part, a gear shaping cutter, and a tool connecting rod, wherein: the blocking body is inserted into the clamping body by fitting, the clamping body is provided with small holes around, the clamping body is provided with a U-shaped notch, the positioning plate is mounted on the clamping body by means of a hexagon socket cylindrical head screw, the spline part is positioned and mounted on the positioning plate by means of a positioning spindle, and the gear shaping cutter is connected to the main shaft of the gear shaping machine by means of a tool connecting rod; a gear shaping method for internal spline parts of aviation with small module, comprising the following steps: a. installation and alignment of the gear shaping cutter; b. installation and alignment of the workpiece; c. workpiece processing; d. workpiece detection; the disadvantage of this patent is that it is necessary to design special auxiliary tooling for alignment, which greatly increases the processing cost and processing time. Summary of the invention

[0005] The present invention mainly aims at the problem that the CNC chamfering method of spline surface in the prior art needs to design some auxiliary tooling or fixtures to complete the angular positioning of the spline, which greatly increases the tooling cost and time cost of the spline chamfering. A spline surface chamfering method with spline angular self-positioning is proposed.

[0006] In view of the above problems, the technical solution of the present invention is as follows:

[0007] A method for rounding a spline surface with self-positioning angular spline, comprising the following steps:

[0008] S1. A keyway is provided on the disc gear shaping cutter, wherein the keyway has an angular relationship consistent with any tooth of the gear shaping cutter, and a matching key is designed on the gear shaping cutter bar so that the gear shaping cutter has an angular relationship consistent with the machine tool; the part is fixed on the CNC machining center by designing a fixture with a locating pin;

[0009] S2. Before gear shaping, at least one positioning hole is processed on the part, and the positioning hole is used for the part to cooperate with the positioning pin of the gear shaping fixture during gear shaping;

[0010] S3. During gear shaping, the cutting point of the gear shaping cutter is fixed at a certain position of the spline to be processed on the part through the machine tool control program, and then the spline chamfering process is performed. The part is fixed by designing a fixture with a locating pin. The locating hole of the part is consistent with the locating hole installed in the gear shaping process. Finally, a forming column milling cutter that matches the chamfering size of the spline profile is used to chamfer the spline profile.

[0011] Furthermore, in the step S1, the gear shaping cutter and the gear shaping cutter bar are connected via a keyway according to the interface type of the gear shaping machine tool, so that the angular relationship between the gear shaping cutter and the gear shaping cutter bar remains unchanged.

[0012] Furthermore, a common flat key is opened at the inner hole of the gear shaping cutter, or an end face keyway is opened at the end of the gear shaping cutter away from the blade.

[0013] Furthermore, the keyway is angularly consistent with any slotting tooth of the slotting cutter.

[0014] Furthermore, in the step S1, the key is provided on the mating surface of the gear shaping cutter and the gear shaping cutter rod.

[0015] Furthermore, in step S2, the positioning pin is a diamond pin or a cylindrical pin.

[0016] Furthermore, in step S3, the part is set on the gear shaping fixture, the part positioning hole is inserted into the positioning pin of the gear shaping fixture, and the alignment fixture and the part positioning plane runout is no more than 0.015mm.

[0017] Furthermore, the part is fixed to the gear-slotting fixture by means of a split washer and a hexagonal nut, and the runout of the upper end surface of the part is checked to be no greater than 0.01 mm.

[0018] Furthermore, in step S3, the arc radius R of the forming column milling cutter is 0.2, the diameter ФA is 0.8 mm, and the tool processing depth L is 0.55 mm.

[0019] Furthermore, the diameter of the forming column milling cutter is set to 0.8mm, the processing depth is 0.55mm, the tool speed is 5000r / min, the feed is F100mm / min, the processing tool path is selected as the entire internal spline surface; the milling starting point is the square root circle of the X-axis.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention aims at the splines to be processed by slotting, and sets a keyway on the disc gear slotting cutter, and ensures that the angular relationship between the keyway and any tooth of the gear slotting cutter is consistent, and then designs a matching key on the gear slotting cutter bar, so that the angular relationship between the gear slotting cutter and the machine tool is consistent; by designing a fixture with a locating pin, the part is fixed on the CNC machining center, so that the spline can be self-positioned to complete the spline chamfering; the processing efficiency of this method is high. Compared with the use of spline alignment tooling, the present invention only needs to fix the spline angular direction on necessary tools such as the gear slotting cutter, the gear slotting cutter bar and the clamping fixture, which saves the tooling cost and greatly shortens the time required to align the spline angular position before the spline profile is chamfered.

[0022] 2. The method of the present invention has wide applicability and can be used in other spline forming processes such as gear grinding and gear pulling. It only needs to ensure that the angular relationship between the parts in the spline forming process and the spline surface rounding process is fixed.

[0023] 3. In addition to being used for chamfering spline surfaces, the method of the present invention can also be used for chamfering gear surfaces or similar special surfaces. If a forming chamfering cutter is used, it can also be used for chamfering special surfaces. For chamfering of spline surfaces of smaller parts, a one-machine-multiple-clamp tool can be designed. It is only necessary to ensure that each part is connected to the fixture through the locating holes in the same position, and the spline chamfering of multiple parts can be completed. This process is not affected by whether the machine tool is vertical or horizontal. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of gear shaping processing of the present invention;

[0025] Figure 2 It is a schematic diagram of a face keyway gear shaping cutter according to the present invention;

[0026] Figure 3 A bottom view of the end face keyway shaping cutter of the present invention;

[0027] Figure 4 It is a schematic diagram of the assembly of the gear shaping cutter bar and the gear shaping cutter of the present invention;

[0028] Figure 5 It is a schematic diagram of parts clamping of the present invention;

[0029] Figure 6It is the structural diagram of the forming column milling cutter of the present invention;

[0030] Figure 7 This is the tool path diagram for internal spline surface milling of the present invention.

[0031] In the above figure, 1, diamond pin; 2, gear shaping base; 3, cylindrical pin, 4, locating shaft; 5, hexagon socket head screw; 6, base; 7, bolt; 8, hexagonal thin nut; 9, open washer; 10, shouldered hexagonal nut; 11, part; 12, gear shaping cutter bar; 13, gear shaping cutter; 14, forming column milling cutter; 15, spline; 16, angular locating end; 17, supporting end; 18, fixed end; 19, locating end. DETAILED DESCRIPTION

[0032] In order to clearly illustrate the technical features of the application scheme of the present invention, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0034] In addition, in the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0035] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] Example 1

[0037] like Figures 1 to 7 As shown, a method for rounding a spline profile with self-positioning angular spline includes the following steps:

[0038] S1. A keyway is provided on the disc gear shaping cutter, wherein the keyway has an angular relationship consistent with any tooth of the gear shaping cutter 13, and a matching key is designed on the gear shaping cutter rod 12, so that the gear shaping cutter 13 has an angular relationship consistent with the machine tool; a fixture with a locating pin is designed to fix the part 11 on the CNC machining center; during the actual machining process, the part 11 is fixed on the machine tool by the fixture with a locating pin, and the lowering position of the gear shaping cutter 13 is controlled at a fixed position, so that the angular relationship of the spline 15 processed by the part 11 with respect to the locating hole is always consistent, and the replacement of the part 11 or the gear shaping cutter 13 will not be affected;

[0039] S2. Before gear shaping, at least one positioning hole is formed on the part 11, and the positioning hole is used for the part 11 to cooperate with the positioning pin of the gear shaping fixture during gear shaping;

[0040] S3. During gear shaping, the lower cutting point of the gear shaping cutter 13 is fixed at a certain position of the spline to be processed on the part through the machine tool control program, and then the spline chamfering is performed. The part 11 is fixed by designing a fixture with a locating pin, and the part locating hole is consistent with the locating hole installed in the gear shaping process. Finally, a forming column milling cutter 14 that matches the chamfering size of the spline profile is used. The tool path for processing the spline required is selected in the programming software and the G code is generated, so that the spline profile chamfering with self-positioning of the spline can be realized.

[0041] like Figure 1 As shown, in this embodiment, first connect the gear shaping base 2 to the gear shaping machine base, connect the gear shaping fixture (an integral structure except for the nut and washer in the attached figure) to the gear shaping base 2, and tighten the three hexagon socket head screws 5; place the part 11 on the gear shaping fixture, insert the part positioning hole into the diamond pin 1 of the gear shaping fixture, and align the fixture and the part positioning plane to ensure that the runout is no more than 0.015mm; install and tighten the three open washers 9 and the shouldered hexagonal nut 10, fix the part 11 on the gear shaping fixture, and check that the runout of the upper end surface of the part 11 is no more than 0.01mm; start the machine tool, and use the gear shaping cutter 13 with angular positioning and the gear shaping cutter bar 12 to start shaping the spline.

[0042] In the actual processing process, the part 11 is fixed on the machine tool by a fixture with a locating pin, and the cutting position of the gear shaping cutter 13 is controlled at a fixed position, so that the angular relationship of the spline processed by the part 11 with respect to the locating hole is always consistent and is not affected by the replacement of the part 11 or the gear shaping cutter 13; by designing a fixture with a locating pin to fix the part 1, it is no longer necessary to align the angular direction of the spline 15 in the subsequent spline surface rounding process, thereby realizing the spline surface rounding process in which the spline 15 can be self-positioned.

[0043] like Figure 2 , Figure 3 and Figure 4 As shown, in order to ensure that the gear shaping cutter 13 matches the gear shaping cutter bar 12, according to the interface type of the gear shaping machine tool, a special gear shaping cutter bar 12 is designed to match its keyway, as shown in FIG. Figure 2 As shown, the mating surfaces of the gear shaping cutter rod 12 and the gear shaping cutter 13 have matching keys; a keyway is opened on the end surface of the gear shaping cutter 13 away from the blade end to increase the rigidity of the gear shaping cutter 13. It should be noted that the keyway must be consistent with the angular direction of any cutting tooth of the gear shaping cutter 13.

[0044] Example 2

[0045] like Figures 1 to 7 As shown, a method for rounding a spline profile with self-positioning angular spline includes the following steps:

[0046] S1. A keyway is provided on the disc gear shaping cutter, wherein the keyway has an angular relationship consistent with any tooth of the gear shaping cutter 13, and a matching key is designed on the gear shaping cutter rod 12, so that the gear shaping cutter 13 has an angular relationship consistent with the machine tool; a fixture with a locating pin is designed to fix the part 11 on the CNC machining center; during the actual machining process, the part 11 is fixed on the machine tool by the fixture with a locating pin, and the lowering position of the gear shaping cutter 13 is controlled at a fixed position, so that the angular relationship of the spline 15 processed by the part 11 with respect to the locating hole is always consistent, and the replacement of the part 11 or the gear shaping cutter 13 will not be affected;

[0047] S2. Before gear shaping, at least one positioning hole is formed on the part 11, and the positioning hole is used for the part 11 to cooperate with the positioning pin of the gear shaping fixture during gear shaping;

[0048] S3. During gear shaping, the lower cutting point of the gear shaping cutter 13 is fixed at a certain position of the spline to be processed on the part through the machine tool control program, and then the spline chamfering is performed. The part 11 is fixed by designing a fixture with a locating pin, and the part locating hole is consistent with the locating hole installed in the gear shaping process. Finally, a forming column milling cutter 14 that matches the chamfering size of the spline profile is used. The tool path for processing the spline required is selected in the programming software and the G code is generated, so that the spline profile chamfering with self-positioning of the spline can be realized.

[0049] like Figure 4 As shown, in this embodiment, the diameter of the part 11 is Φ369mm and the length is about 165mm. The spline at the part that needs to be chamfered is an internal spline, which is located at the end face of the large end of the part 11, has 75 teeth, a module of 2.5, a pressure angle of 30°, a major diameter of Φ191, a minor diameter of Φ185, a tooth root radius of R0.5, and a spline surface chamfering requirement of R0.2. Both the gear shaping and the spline surface chamfering are processed vertically. The clamping method of the part 11 is as follows Figure 5 As shown, the bottom of the part 11 is used as the positioning end 19 for positioning, and an angular positioning hole is provided on the left side of the part 11 as the angular positioning end 16, and the part 11 is fixed and supported by a clamp.

[0050] Example 3

[0051] like Figures 1 to 7 As shown, a method for rounding a spline profile with self-positioning angular spline is provided. In this embodiment, the rounding process of the spline profile is similar to Figure 1 Basically the same, except that the gear shaping base 2 needs to be changed to a base plate for CNC machining. The base plate is matched with the vertical machining center platform and fastened together by screws. The specific steps of chamfering are as follows:

[0052] (1) First, connect the gear shaping base 2 to the gear shaping machine base, connect the gear shaping fixture (in the attached figure, it is an integral structure except for the nut and washer) to the gear shaping base 2, and tighten the three hexagon socket head screws 5; place the part 11 on the gear shaping fixture, insert the part positioning hole into the diamond pin 1 of the gear shaping fixture, and align the fixture and the positioning plane of the part 11 to ensure that the runout is no more than 0.015mm; install and tighten the three open washers 9 and the shouldered hexagonal nut 10, fix the part 11 on the gear shaping fixture, and check that the runout of the upper end surface of the part 11 is no more than 0.01mm; start the machine tool, and use the gear shaping cutter 13 with angular positioning and the gear shaping cutter bar 12 to start shaping the spline; (2) Use a forming column milling cutter 14, such as Figure 6 As shown, the arc radius R is 0.2, the diameter ФA is 0.8mm, and the tool processing depth L is 0.55mm. Therefore, in the programming software, it is only necessary to set the diameter of the forming column milling cutter 14 to 0.8mm, the processing depth to 0.55mm, and the processing tool path to be selected as the entire internal spline profile; (3), as Figure 7 As shown, select the tool path for processing the spline in the programming software and generate the G code. The milling starting point can be the square root circle of the X-axis, so that the chamfering of the spline surface inside the entire part 11 can be completed; loosen the nut, re-clamp and align the part 11, and then the spline surface chamfering can be directly performed.

[0053] Obviously, the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for rounding a spline surface with self-positioning angular spline, characterized in that: The following steps are involved: S1. A keyway is provided on the disc gear shaping cutter, wherein the keyway has an angular relationship consistent with any tooth of the gear shaping cutter, and a matching key is designed on the gear shaping cutter bar so that the gear shaping cutter has an angular relationship consistent with the machine tool; the part is fixed on the CNC machining center by designing a fixture with a locating pin; S2. Before gear shaping, at least one positioning hole is processed on the part, and the positioning hole is used for the part to cooperate with the positioning pin of the gear shaping fixture during gear shaping; S3. During gear shaping, the cutting point of the gear shaping cutter is fixed at a certain position of the spline to be processed on the part through the machine tool control program, and then the spline chamfering process is performed. The part is fixed by designing a fixture with a locating pin. The locating hole of the part is consistent with the locating hole installed in the gear shaping process. Finally, a forming column milling cutter that matches the chamfering size of the spline profile is used to chamfer the spline profile.

2. A method for rounding a spline surface with angular self-positioning according to claim 1, characterized in that: In the step S1, the gear shaping cutter and the gear shaping cutter bar are connected via a keyway according to the interface type of the gear shaping machine tool, so that the angular relationship between the gear shaping cutter and the gear shaping cutter bar remains unchanged.

3. A method for rounding a spline surface with angular self-positioning according to claim 2, characterized in that: A common flat key is opened at the inner hole of the gear shaping cutter, or an end face keyway is opened at the end of the gear shaping cutter away from the cutting edge.

4. A method for rounding a spline surface with angular self-positioning according to claim 3, characterized in that: The keyway is consistent with the angular direction of any slotting tooth of the gear slotting cutter.

5. The method for rounding the spline surface with angular self-positioning of the spline according to claim 1, characterized in that: In the step S1, the key is arranged on the mating surface of the gear shaping cutter and the gear shaping cutter rod.

6. A method for rounding a spline surface with angular self-positioning according to claim 1, characterized in that: In step S2, the positioning pin is a diamond pin or a cylindrical pin.

7. A method for rounding a spline surface with angular self-positioning according to claim 1, characterized in that: In step S3, the part is set on the gear shaping fixture, the part positioning hole is inserted into the positioning pin of the gear shaping fixture, and the alignment fixture and the part positioning plane runout is no more than 0.015mm.

8. A method for rounding a spline surface with angular self-positioning according to claim 7, characterized in that: Fix the part to the gear clamp with a split washer and a hexagonal nut, and check that the runout of the upper end surface of the part is no more than 0.01mm.

9. A method for rounding a spline surface with angular self-positioning according to claim 1, characterized in that: In step S3, the arc radius R of the forming column milling cutter is 0.2, the diameter ФA is 0.8 mm, and the tool processing depth L is 0.55 mm.

10. A method for rounding a spline surface with angular self-positioning according to claim 9, characterized in that: The diameter of the forming column milling cutter is set to 0.8mm, the processing depth is 0.55mm, the tool speed is 5000r / min, the feed is F100mm / min, and the processing tool path is selected as the entire internal spline profile; the milling starting point is the square root circle of the X-axis.

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