Translational helical tooth trace bevel gear and machining method

Abstract

The invention discloses a translational helical-tooth-trace bevel gear and a processing method, the tooth trace of the translational helical-tooth-trace bevel gear is a translational spiral line after being unfolded along an indexing conical surface, the translational spiral line is formed by a tool rotating circle and a corresponding translational angle around the cone top of the bevel gear, and the gear teeth of the bevel gear are provided with concave tooth surfaces and convex tooth surfaces; efficient machining of the gear can be achieved, and the gear machining precision is slightly affected by the tool mounting precision; the problems that in the prior art, bevel gear machining efficiency is low, and the machining precision is greatly influenced by tool installation precision are solved.

Description

Technical Field

[0001] The invention relates to the technical field of bevel gear processing, in particular to a translational spiral tooth line bevel gear and a processing method thereof. Background Art

[0002] Bevel gear transmission is a more complex type of intersecting axis transmission among gear transmission types. Among them, spiral bevel gears have the advantages of high load bearing capacity, noise and vibration reduction, good lubrication performance, and long life. They are currently widely used in many fields such as automobile industry, aerospace, power engineering, and mechanical engineering. However, among the current bevel gear processing methods, disc tooth-by-tooth milling requires tooth-by-tooth processing, which has low processing efficiency; although the continuous indexing method for processing bevel gears is more efficient, the accuracy is affected by the installation accuracy of multiple blades, and the processing accuracy is difficult to guarantee. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the above and / or existing problems in the processing of existing bevel gears, the present invention is proposed.

[0005] Therefore, the purpose of the present invention is to provide a translational spiral tooth line bevel gear and a processing method, wherein a plurality of tools are arranged on the cutter disc according to a spiral line, and the cutter disc rotates one circle and the plurality of tools sequentially process the same tooth groove. When the cutter disc rotates a second circle, due to the relative motion relationship that the tooth blank rotates one tooth for one circle of the cutter disc, the tool processes the next tooth groove, thereby realizing continuous processing. In this way, during processing, it is ensured that all tooth grooves are cut and formed by the same set of tools installed on the cutter disc, thereby avoiding the influence of the tooth pitch accuracy due to the tool installation error and improving the tooth pitch accuracy of the gear.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a bevel gear with a translatory spiral tooth line, wherein the tooth line of the bevel gear with a translatory spiral tooth line is a translatory spiral line after being unfolded along the dividing cone surface, and the translatory spiral line is formed by the corresponding angle of the circular additional translation of the tool around the cone top of the bevel gear, and the teeth of the bevel gear have concave tooth surfaces and convex tooth surfaces.

[0007] Another object of the present invention is to provide a method for processing a translational spiral tooth line bevel gear, wherein: a translational spiral tooth line bevel gear is processed using a processing device, the processing device comprises a frame, a bracket indexing plate is connected to the frame, an L-shaped bracket is rotatably connected above the bracket indexing plate, a rotating shaft for connecting a gear blank is rotatably connected to the L-shaped bracket, a cutter disc is rotatably connected to the frame above the rotating shaft, and a plurality of cutters are arranged on the periphery of the cutter disc; the following steps are included: The tool is set so that the rotating plane of the tool tip is tangent to the conical surface of the root of the tooth blank at the root of the large end. At this point of tangency, the angle between the circular trajectory formed by the rotation of the main tool center and the tangent of the root circle of the large end is γ; Perform deep cutting and adjust the cutter head speed ω T and gear blank speed ω G ,make ω T / ω G =1 / Z Each time the cutter head rotates one circle, the next tooth groove is processed in turn. After the gear blank rotates one circle, the gear blank is fed in the tooth height direction. According to the feed amount and gear parameters, the bevel gear is cut deep after the gear blank rotates multiple circles. After the tooth groove cutting is completed, the gear blank is directly expanded.

[0008] As a preferred solution of the processing method of the translational spiral bevel gear in the present invention, the process of the generating process is: The meshing rotation of the virtual gear is achieved by simulating the gear blank and the tool. The straight line where the rotation center of the virtual gear passes through the cone top of the bevel gear. The rotation of the gear blank is achieved by ω G Additional speed based on ω a The rotation of the virtual gear is realized by the bracket indexing plate driving the gear blank to rotate relative to the virtual gear, and the speed is ω m ,ensure ω m / ω a =cosδ , δ The pitch cone angle of the bevel gear to be processed is set so that the tooth blank and the virtual forming wheel are relatively meshed and transmitted. The left and right tooth surfaces are continuously developed. After the left and right tooth surfaces are developed, press ω a , ω m After turning back to the positive gear blank and the bracket dividing plate, the right tooth surface and the left tooth surface are continued to be developed.

[0009] As a preferred solution of the processing method of the translational spiral tooth bevel gear in the present invention, wherein: the bracket dividing plate includes a horizontally arranged horizontal connecting part, a vertically arranged vertical part is fixed on the upper side of the horizontal connecting part, a transmission box is fixedly connected to the upper side of the vertical part, the L-shaped bracket includes a rotating part rotatably connected to the vertical part, an inclined connecting part is fixed on the lower side of the rotating part, the rotating shaft is rotatably connected above the inclined connecting part, an adjusting motor is fixedly connected to the outside of the transmission box, a power output shaft is rotatably connected to the transmission box, the adjusting motor and the power output shaft are transmission-connected, and the power output shaft is connected to the rotating part.

[0010] As a preferred solution of the processing method of the translational spiral bevel gear in the present invention, wherein: a gear blank dividing plate is fixedly connected to the upper side of the inclined connection portion, and the rotating shaft is rotatably connected to the gear blank dividing plate.

[0011] As a preferred solution of the processing method of the translational spiral bevel gear in the present invention, wherein: a plurality of mounting grooves are arranged on the periphery of the cutter disc, the cutter disc is fixedly connected to a cutter rod via the mounting grooves, and the cutter is fixedly connected to the lower part of the cutter rod.

[0012] As a preferred solution of the processing method of the translational spiral bevel gear in the present invention, before the deep cutting processing, the following steps are also included: Adjust the position of the bracket indexing plate to activate the adjusting motor, and the L-shaped bracket rotates, driving the gear blank indexing plate to rotate. When the angle between the straight line where the rotation center of the gear blank is located and the horizontal plane of the cutter disc is the pitch cone angle, the transmission motor stops.

[0013] Compared with the prior art, the present invention has the following technical effects: it can realize efficient processing of gears, and the gear processing accuracy is less affected by the tool installation accuracy; it solves the problem of low bevel gear processing efficiency and great influence of tool installation accuracy on processing accuracy in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them: Figure 1 The three-dimensional structure diagram of the translational spiral tooth bevel gear prepared by using the present invention.

[0015] Figure 2 It is a schematic diagram of the production principle of a translational spiral bevel gear.

[0016] Figure 3It is a schematic diagram of the structural principle of the simplified processing device in the present invention (when the L-shaped bracket is in the initial position).

[0017] Figure 4 It is a schematic diagram of the structural principle of a simplified processing device (after position adjustment before processing) in the present invention.

[0018] Figure 5 It is a schematic diagram of the angle between the circular trajectory formed by the rotation of the main tool center and the tangent line of the large end tooth root circle in the present invention.

[0019] Figure 6 This is a schematic diagram of the principle of forming the translational helical tooth line in the present invention.

[0020] Figure 7 It is a schematic diagram of the translational helical tooth line in the present invention.

[0021] Figure 8 It is a three-dimensional structural diagram of the processing device in the present invention.

[0022] Fig. 9 for Figure 8 A partial enlarged view of point A in the middle.

[0023] Fig.10 This is a top view of several cutting tools installed on the cutter disc in the processing device.

[0024] Fig.11 It is a schematic diagram of the meshing of a pair of translational spiral bevel gears in the present invention.

[0025] In the figure, 100 is a bevel gear, 101 is a concave tooth surface, 102 is a convex tooth surface, 200 is a processing device, 201 is a lifting linear drive, 202 is a lifting rod, 203 is a Z-axis slide, 204 is a Y-axis slide, 205 is a motor seat, 205a is a mounting cavity, 206 is a frame, 207 is an X-axis slide, 208 is a driving motor, 209 is a bracket dividing plate, 209a is a horizontal connecting part, 209b is a vertical part, 210 is an adjusting motor, 211 is an L-shaped bracket, 211a is an inclined connecting part, 211b is a rotating part, 212 is a transmission box, 213 is a tool rod, 214 is a tool disc, 214a is a mounting groove, 215 is a connecting motor, 216 is a tool, 217 is a rotating shaft, 218 is a gear blank dividing plate, and 219 is a virtual forming wheel dividing plate; 1 is a convex tooth surface of a translational spiral tooth line bevel gear, and 2 is a concave tooth surface of a translational spiral tooth line bevel gear. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0027] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0028] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0029] Example 1 Reference Figure 1 and Fig.11 , which is the first embodiment of the present invention, provides a translational spiral bevel gear with a large load-bearing capacity.

[0030] A translational spiral tooth bevel gear 100, the tooth line of the translational spiral tooth bevel gear 100 is a translational spiral line after being unfolded along a dividing cone surface, the translational spiral line is formed by a tool 216 rotating in a circle and additionally translating around the cone top of the bevel gear at a corresponding angle, the gear teeth of the bevel gear 100 have a concave tooth surface 101 and a convex tooth surface 102, the tooth line curvature radius of the concave tooth surface 101 is equal to or slightly larger than the tooth line curvature radius of the convex tooth surface 102, forming a micro-drum-shaped gear tooth, the tooth line curvature radius of the convex and concave tooth surface 101 is controlled by the corresponding blade rotation radius, a pair of left-handed and right-handed translational spiral tooth bevel gears 100 are required to cooperate when meshing, the meshing contact area of ​​the translational spiral tooth bevel gear 100 is an elongated elliptical area, which can improve the load-bearing capacity of the bevel gear.

[0031] Example 2 refer to Figure 2 to Figure 10 This embodiment is based on the embodiment 1, and provides a processing method of a translational spiral tooth bevel gear 100, by which the translational spiral tooth bevel gear 100 can be processed.

[0032] Specifically, a processing device 200 is used to process a translational spiral tooth bevel gear 100, the processing device 200 includes a frame 206, a bracket indexing plate 209 is connected to the frame 206, the bracket indexing plate 209 includes a horizontally arranged horizontal connecting portion 209a, a vertically arranged vertical portion 209b is fixed on the upper side of the horizontal connecting portion 209a, a transmission box 212 is fixedly connected to the upper side of the vertical portion 209b, an L-shaped bracket includes a rotating portion 211b rotatably connected to the vertical portion 209b, an inclined connecting portion 211a is fixed on the lower side of the rotating portion 211b, the rotation center axis of the rotating portion 211b just passes through the cone top of the bevel gear, a rotating shaft 217 is rotatably connected above the inclined connecting portion 211a, an adjusting motor 210 is fixedly connected to the outer side of the transmission box 212, a power output shaft is rotatably connected to the transmission box 212, the adjusting motor 210 is transmission-connected to the power output shaft, the power output shaft is connected to the rotating portion 211b, and the inclined A gear blank indexing plate 218 is fixedly connected to the upper side of the connecting portion 211a, and a connecting motor 215 is fixedly connected to the outer side of the gear blank indexing plate 218. A rotating shaft 217 for connecting the gear blank is rotatably connected to the gear blank indexing plate 218, and the connecting motor 215 and the rotating shaft 217 are transmission-connected (the gear blank indexing plate 218 is equivalent to a small transmission box 212, and the structure for realizing the transmission connection between the connecting motor 215 and the rotating shaft 217 is not drawn, which is a prior art and not an improvement point of the present application). A motor seat 205 having a mounting cavity 205a is fixedly connected to the frame 206 above the rotating shaft 217, and a processing motor is fixedly connected in the mounting cavity 205a of the motor seat 205. A cutter disc 214 is connected to the processing motor, and a plurality of mounting grooves 214a are arranged on the outer periphery of the cutter disc 214. The cutter disc 214 is fixedly connected to a tool rod 213 through the mounting groove 214a. A tool 216 is fixedly connected to the lower part of the tool rod 213. The installation trajectory of the tool 216 is as shown in FIG. Fig.10 The middle cutter 216 is installed with a helical line arrangement to ensure that the helical line pitch is the same as the pitch of the large end of the gear blank; comprising the following steps, Adjust the position of the bracket indexing plate 209 to activate the adjusting motor 210, and the L-shaped bracket rotates, driving the gear blank indexing plate 218 to rotate. When the angle between the straight line where the rotation center of the gear blank is located and the horizontal plane of the cutter head 214 is the pitch cone angle, the transmission motor stops. The tool is set so that the rotating plane of the tool tip 216 is tangent to the conical surface of the tooth root of the gear blank at the large end tooth root. At this tangent point, the angle between the circular trajectory formed by the central rotation of the main tool 216 and the tangent line of the large end tooth root circle is γ. The selection of γ affects the helix angle of the translational spiral tooth line bevel gear 100. The larger γ is, the smaller the helix angle is, and the smaller the overlap of the bevel gear is. Carry out deep cutting and adjust the speed of the cutter head 214ω T and gear blank speed ω G , so that ω T / ω G=1 / Z, the cutter head 214 processes the next tooth groove in turn every time it rotates one circle, and the tooth blank makes a feeding motion in the tooth height direction after rotating one circle. According to the feed amount and gear parameters, the bevel gear is cut deep after the tooth blank rotates multiple circles. After the tooth groove cutting is completed, the gear blank is directly subjected to the expansion processing; The process of unfolding is: The meshing rotation of the virtual forming gear is achieved by simulating the tooth blank and the tool 216. The straight line where the rotation center of the virtual forming gear is located passes through the cone top of the bevel gear. The rotation of the tooth blank is achieved by adding an additional speed ωa to the original speed ωG. The rotation of the virtual forming gear is achieved by the bracket dividing plate 209 driving the tooth blank to rotate relative to the virtual forming gear. The speed is ωm, ensuring that ωm / ωa=cosδ, where δ is the pitch angle of the processed bevel gear, so that the tooth blank and the virtual forming wheel are relatively meshed and transmitted, and the left and right tooth surfaces are developed continuously. After the development of the left and right tooth surfaces is completed, the tooth blank and the bracket dividing plate 209 are turned back to the positive direction according to ωa and ωm, and the development of the right and left tooth surfaces continues.

[0033] A plurality of cutters 216 are arranged on the cutter disc 214 in a spiral line, and the cutter disc 214 is a trapezoidal cutter 216. When the cutter disc 214 rotates one circle, the plurality of cutters 216 process the same tooth groove in sequence. When the cutter disc 214 rotates the second circle, due to the relative motion relationship that the cutter disc 214 rotates one tooth per circle, the cutter 216 processes the next tooth groove, thereby realizing continuous processing. In this way, during processing, it can be ensured that all tooth grooves are cut and formed by the fixed position cutters 216 installed on the cutter disc 214, and the pitch accuracy of the gear can be improved.

[0034] In order to facilitate feeding or tool setting, a Z-axis slide that can move in the height direction is slidably connected to the frame 206, a Y-axis slide that can move forward and backward is slidably connected to the upper end of the Z-axis slide, and an X-axis slide that can move left and right is slidably connected to the upper end of the Y-axis slide. The structures for realizing the X-axis slide, the Y-axis slide and the Z-axis slide are all prior art, which are not improvements of the present application. Among them, the present embodiment provides a structure for realizing the lifting of the Z-axis slide, specifically, a lifting linear drive 201 is fixedly connected to the lower part of the frame 206, which is prior art, and a hydraulic cylinder is preferably used in the present application. The lifting linear drive 201 is connected to a lifting rod 202 that can perform reciprocating linear motion in the height direction. The Z-axis slide is fixedly connected to the upper end of the lifting rod 202; the upper side of the X-axis slide is fixedly connected to a virtual shape-generating wheel dividing plate 219, the outer side of the virtual shape-generating wheel dividing plate 219 is fixedly connected to a drive motor 208, and the virtual shape-generating wheel dividing plate 219 is rotatably connected to a rotating shaft, and the drive motor 208 and the rotating shaft are transmission-connected (the virtual shape-generating wheel dividing plate 219 can be regarded as a transmission box 212, and the structure for realizing the transmission connection between the drive motor 208 and the rotating shaft is a prior art, and is not an improvement point of the present application), and the bracket dividing plate 209 is connected to the rotating shaft.

[0035] The gear blank and the tool 216 are aligned by adjusting the positions of the Y-axis slide, the X-axis slide and the Z-axis slide. During processing, the feed amount is adjusted by adjusting the height of the Z-axis slide.

[0036] The Z-axis slide controls the feed of the cutter head 214, and the power output shaft B2 of the L-shaped bracket passes through the cone top of the bevel gear. When the gear blank is in the initial position (such as Figure 3 As shown); the virtual forming wheel indexing plate 219 coincides with the rotating shaft B1 and A and passes through the cone top of the bevel gear. During processing, the L-shaped bracket rotates around the power output shaft B2 to drive the gear blank to rotate to Figure 4 The relative position of the cutter disc 214 and the tooth blank is adjusted by the Y-axis slide and the X-axis slide to ensure that the tooth blank rotates one tooth when the cutter disc 214 rotates one circle to realize processing. During the unfolding processing, a speed ωa is added to the original speed of the tooth blank and the tooth blank is rotated ωm around the rotation axis B1. The rotation around the rotation axis 217B1 is generated by the drive motor 208 on the virtual forming wheel dividing plate 219 to ensure that ωm / ωa=cosδ, wherein δ is the pitch cone angle of the bevel gear being processed, so that the tooth blank and the virtual crown forming wheel are relatively meshed for transmission.

[0037] The tooth line equation of the translational spiral tooth line bevel gear 100 in the present invention is solved, as shown in FIG. Figure 5 As shown, the knife disc 214 rotation center is taken as the coordinate origin to establish the knife disc 214 coordinate system X T O T Y T , its X T The intersection point O of the circular trajectory formed by the rotation of the axis through the center of the main tool 216 and the tangent line of the root circle of the large end of the gear blank G , with O G As the coordinate origin, establish the gear blank coordinate system X G O G Y G , its XT axis is collinear with the tangent of the root circle at the large end of the gear blank. G After the generatrix is ​​expanded, it can be known that the cone top O of the bevel gear B In Y G Any point P on the center trajectory of the main tool 216 T In the coordinate system X T O T Y T The parametric coordinate equations in are: .

[0038] Where θ is the point P T Position angle, R TThe installation radius of the main tool 216. During the machining process, the cutter head 214 and the tooth blank rotate at a constant speed ratio, that is, each point on the arc rotates (translates) around a certain point by a corresponding angle, and the shape is similar to a translational helix, such as Figure 5 As shown, it is named as the translational spiral bevel gear 100.

[0039] It can be clearly seen from the above that the processing method of the present invention can be used to efficiently process the translational spiral tooth bevel gear 100.

[0040] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A translational spiral bevel gear, characterized in that: The tooth line of the bevel gear with a translational spiral is a translational spiral line after being unfolded along the dividing cone surface. The translational spiral line is formed by the corresponding angle of the tool rotating circle and additional translation around the cone top of the bevel gear. The teeth of the bevel gear have concave tooth surfaces and convex tooth surfaces.

2. The method for machining a translational spiral bevel gear according to claim 1, characterized in that: A processing device is used to process a translational spiral tooth line bevel gear, the processing device includes a frame, a bracket indexing plate is connected to the frame, an L-shaped bracket is rotatably connected above the bracket indexing plate, a rotating shaft for connecting a gear blank is rotatably connected to the L-shaped bracket, a cutter disc is rotatably connected to the frame above the rotating shaft, and a plurality of cutting tools are arranged on the periphery of the cutter disc. The method comprises the following steps: setting the tool so that the rotating plane of the tool tip is tangent to the conical surface of the tooth root of the gear blank at the large end tooth root, and the angle between the circular trajectory formed by the rotation of the main tool center and the tangent line of the large end tooth root circle at the tangent point is γ; Perform deep cutting and adjust the cutter head speed ω T and gear blank speed ω G ,make ω T / ω G =1 / Z Each time the cutter head rotates one circle, the next tooth groove is processed in turn. After the gear blank rotates one circle, the gear blank is fed in the tooth height direction. According to the feed amount and gear parameters, the bevel gear is cut deep after the gear blank rotates multiple circles. After the tooth groove cutting is completed, the gear blank is directly expanded.

3. The method for processing a translational spiral bevel gear according to claim 2, characterized in that: The process of generating is realized by simulating the meshing rotation of the virtual gear formed by the gear blank and the tool. The straight line where the rotation center of the virtual gear passes through the cone top of the bevel gear, and the rotation of the gear blank is realized by the original speed. ω G Additional speed based on ω a The rotation of the virtual gear is realized by the bracket indexing plate driving the gear blank to rotate relative to the virtual gear, and the speed is ω m ,ensure ω m / ω a =cosδ , δ The pitch cone angle of the bevel gear to be processed is set so that the tooth blank and the virtual forming wheel are relatively meshed and transmitted. The left and right tooth surfaces are continuously developed. After the left and right tooth surfaces are developed, press ω a , ω m After turning back to the positive gear blank and the bracket dividing plate, the right tooth surface and the left tooth surface are continued to be developed.

4. The method for machining a translational spiral bevel gear according to claim 2, characterized in that: The bracket dividing plate includes a horizontally arranged horizontal connecting part, a vertically arranged vertical part is fixed on the upper side of the horizontal connecting part, a transmission box is fixedly connected to the upper side of the vertical part, the L-shaped bracket includes a rotating part rotatably connected to the vertical part, an inclined connecting part is fixed on the lower side of the rotating part, the rotating shaft is rotatably connected above the inclined connecting part, an adjusting motor is fixedly connected to the outer side of the transmission box, a power output shaft is rotatably connected to the transmission box, the adjusting motor and the power output shaft are transmission-connected, and the power output shaft is connected to the rotating part.

5. The method for machining a translational spiral bevel gear according to claim 4, characterized in that: A gear blank dividing plate is fixedly connected to the upper side of the inclined connection portion, and the rotating shaft is rotatably connected to the gear blank dividing plate.

6. The method for machining a translational spiral bevel gear according to claim 2, characterized in that: A plurality of mounting grooves are arranged on the outer circumference of the cutter disc, and the cutter disc is fixedly connected to a cutter rod via the mounting grooves, and the cutter is fixedly connected to the lower part of the cutter rod.

7. The method for machining a translational spiral bevel gear according to claim 4, characterized in that: Before deep cutting, the following steps are also included: adjusting the position of the bracket indexing plate to activate the adjustment motor, rotating the L-shaped bracket, driving the gear blank indexing plate to rotate, and when the angle between the straight line where the rotation center of the gear blank is located and the horizontal plane of the cutter disc is the pitch cone angle, the transmission motor stops moving.

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