Gear shaft hobbing and damping tool
By using mounting brackets and radial limiting structures in the gear hobbing process, the problem of excessive gear runout tolerance was solved, and radial and axial positioning of the gear shaft was achieved, ensuring machining accuracy and force balance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGZHOU FULIN PRECISION TRANSMISSION CO LTD
- Filing Date
- 2025-07-07
- Publication Date
- 2026-07-14
AI Technical Summary
During gear hobbing, the gear blank is axially positioned only by the front and rear centers, which causes the runout tolerance of some gears after machining to exceed the design tolerance range.
A gear rolling vibration damping fixture is adopted, including two mounting brackets and two radial limiting structures. Rolling elements and dampers are used to radially and axially position the gear blank, ensuring that the symmetrical center line of the rolling plate is on the same straight line as the rotation center of the gear blank, and the vibration energy is consumed by the damper.
This ensures that the runout tolerance of the gear shaft after machining is within the design range, improves the versatility of the tooling and machining accuracy, suppresses the radial vibration amplitude of the gear shaft, and ensures the radial force balance of the gear shaft.
Smart Images
Figure CN224487871U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of tooling structures, specifically to a gear shaft rolling vibration damping tooling. Background Technology
[0002] In gear hobbing, the relative motion between a pair of hobbing plates (upper and lower, each with involute teeth) and the workpiece is used to machine the gear profile. The lower and upper hobbing plates reciprocate linearly, with the gear blank to be machined placed between the two hobbing plates. As the hobbing plates move, their teeth gradually press against the outer surface of the workpiece, causing the workpiece material to flow through plastic deformation of the metal, ultimately forming a gear tooth profile that perfectly matches the tooth profile of the hobbing plates.
[0003] Currently, during gear rolling, the front and rear ends of the gear shaft are positioned by the front and rear centers, respectively. This means that the gear shaft blank is only axially positioned. The center lines of symmetry of the two rolling plates may not be on the same straight line as the rotation center of the gear shaft blank, which causes the runout tolerance of some gear shafts after machining to exceed the design tolerance range. Utility Model Content
[0004] The technical problem this invention aims to solve is that currently, during gear rolling, only the front and rear centers are used to axially position the gear shaft blank, resulting in the runout tolerance of some gear shafts exceeding the design tolerance range after machining. The purpose is to provide a gear rolling vibration damping fixture, in which the outer ring of the rolling element maintains contact with the outer periphery of the gear shaft blank to radially position the gear shaft blank, and works in conjunction with the front and rear centers to axially position the gear shaft blank, thereby achieving simultaneous axial and radial limiting of the gear shaft blank. This ensures that during machining, the symmetrical center lines of the two rolling plates are on the same straight line as the rotation center of the gear shaft blank, thus ensuring that the runout tolerance of the gear shaft is within the design range.
[0005] This utility model is achieved through the following technical solution:
[0006] A gear shaft rolling vibration damping fixture includes two mounting brackets and two radial limiting structures. The two mounting brackets are respectively connected to both sides of the rear center seat. The two radial limiting structures are respectively connected to the lower end of the corresponding mounting brackets and are symmetrical about the vertical line through the center of the gear shaft blank. The free ends of the radial limiting structures are each equipped with a rolling element that can rotate along a preset axis. The rolling element rolls under the drive of the gear shaft. The two rolling elements are respectively located at the lower end of the gear shaft blank, and the outer periphery of the rolling element is in contact with the gear shaft blank.
[0007] The beneficial effects of this utility model are as follows: by connecting the mounting brackets to both sides of the rear center seat, and then connecting the two radial limiting structures to the lower ends of the corresponding mounting brackets in a symmetrical manner, the radial limiting structures are positioned. Rolling elements are also installed at the free ends of the radial limiting structures, and the two rolling elements are located at the lower ends of the gear shaft blank. This facilitates the contact between the outer ring of the rolling elements and the outer circumference of the gear shaft blank during operation, thus radially positioning the gear shaft blank. This ensures that the supporting force of the radial limiting structure on the gear shaft blank is symmetrical, the radial force on the gear shaft blank is balanced, and the front and rear centers work together to axially position the gear shaft blank. This achieves simultaneous axial and radial limiting of the gear shaft blank, ensuring that during processing, the symmetrical center lines of the two tooth-rolling plates are on the same straight line as the rotation center of the gear shaft blank, thereby ensuring that the runout tolerance of the processed gear shaft is within the design range.
[0008] In some embodiments, the radial limiting structure includes a support frame and a damper. One end of the support frame is connected to a mounting bracket, and the other end is connected to one end of the damper. The rolling element is connected to the free end of the damper. By installing the damper on the support frame and mounting the rolling element on the free end of the damper, the vibration energy generated by the gear blank during gear rolling can be dissipated through friction, viscous dissipation, etc., thereby suppressing the radial vibration amplitude of the gear blank. This further ensures that the runout tolerance of the finished gear is within the design range. Furthermore, since the damper can be freely adjusted, it facilitates radial positioning of gear blanks with different diameters, improving the versatility of the tooling.
[0009] In some embodiments, the extension line of the supporting force exerted by the assembly consisting of the damper and rolling elements on the gear shaft blank passes through the centerline of the gear shaft blank. By passing the extension line of the supporting force through the centerline of the gear shaft blank, the gear shaft blank is subjected to force balance, further ensuring that the runout tolerance of the product after machining into a gear shaft is within the design range.
[0010] In some embodiments, the support frame includes a connecting rod and a support plate. The upper end of the connecting rod is connected to the mounting bracket, and the lower end is connected to the support plate. The support plate is inclined, and the damper is mounted on the support plate. By inclinedly setting the support plate, it is convenient to ensure that the extension line of the supporting force generated by the damper and the rolling element passes through the center line of the gear shaft blank.
[0011] In some embodiments, the support plate is provided with a through hole, and the outer periphery of the damper is provided with an external thread. The damper passes through the through hole and engages with the damper nut. This facilitates the replacement and disassembly of the damper.
[0012] In some embodiments, the radial limiting structure further includes a rolling element bracket, which is connected to the end of the damper away from the support plate, and the rolling element is mounted on the rolling element bracket. By providing the rolling element bracket, it is convenient to mount the rolling element on the damper.
[0013] In some embodiments, the rolling element support is Y-shaped, and a rolling element pin is installed at the open end of the rolling element support. The two ends of the rolling element pin are respectively connected to the two side walls of the open end of the rolling element support, and the rolling element shaft hole fits into the rolling element pin. By making the rolling element support Y-shaped and installing the rolling element pin at the open end of the rolling element support, it is convenient to install the rolling element on the rolling element pin, so that the rolling element provides radial support and limitation for the gear shaft blank without affecting its rotation.
[0014] In some embodiments, the vertical portion of the rolling element support is provided with a mounting hole that mates with the phase hole of the damper. A threaded hole is provided on the sidewall of the mounting hole, and the rolling element support mounting screw, after being screwed into the threaded hole, abuts against the damper. This facilitates the removal of the damper by disassembling the mounting screw.
[0015] In some embodiments, the mounting bracket is in the shape of a long strip plate, and is provided with threaded holes and connecting rod mounting holes. The upper end of the connecting rod is provided with a through hole, and the bracket mounting screw passes through the through hole and engages with the threaded hole. The mounting bracket and the connecting rod are connected by the bracket mounting screw for easy disassembly and replacement.
[0016] In some embodiments, the system further includes two support rods, each in the shape of a long strip plate. One end of each support rod is connected to the inner side of a corresponding mounting bracket, and the other end of each rod has an inclined portion. The inclined portion is spaced apart from the outer periphery of the end of the gear shaft blank furthest from the tooth rolling plate. By providing two support plates, the end of the gear shaft blank furthest from the tooth rolling plate is radially supported during operation. The other end, under the cutting force of the tooth rolling plate and the supporting force of the radial limiting structure, ensures that the gear shaft blank is subjected to balanced forces, preventing it from tilting during operation and ensuring that the runout tolerance of the finished gear shaft is within the designed range.
[0017] Compared with the prior art, this utility model has the following advantages and beneficial effects:
[0018] 1. The outer ring of the rolling element maintains contact with the outer circumference of the gear shaft blank to radially position the gear shaft blank, making the supporting force of the radial limiting structure on the gear shaft blank relatively symmetrical. The radial force of the gear shaft blank is balanced, and the front and rear centers work together to axially position the gear shaft blank, thereby achieving simultaneous axial and radial limiting of the gear shaft blank. This ensures that during processing, the symmetrical center line of the two rolling teeth is on the same vertical line as the rotation center of the gear shaft blank, thus ensuring that the runout tolerance of the product after processing into a gear shaft is within the design range.
[0019] 2. The vibration energy generated during the tooth rolling process is dissipated through friction and viscous dissipation by using a damper, thereby suppressing the radial vibration amplitude of the tooth blank and further ensuring that the runout tolerance of the finished tooth shaft is within the design range.
[0020] 3. Furthermore, since the damper can be freely adjusted in position, it is convenient to meet the radial positioning of gear blanks of different diameters, thereby improving the versatility of the tooling.
[0021] 4. The end of the gear shaft blank furthest from the tooth rolling plate is radially supported, while the other end is supported by the cutting force of the tooth rolling plate and the radial limiting structure, so that the gear shaft blank is in overall force balance, preventing the gear shaft blank from tilting during operation and ensuring that the runout tolerance of the product after processing into a gear shaft is within the design range. Attached Figure Description
[0022] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:
[0023] Figure 1 This is a structural diagram of the present invention;
[0024] Figure 2 This is a structural diagram of the present invention from another angle;
[0025] Figure 3 This is a top view of the present invention;
[0026] Figure 4 This is a partial structural diagram of the present invention.
[0027] The attached diagram shows the markings and corresponding component names:
[0028] 1. Gear rolling plate, 2. Front center, 3. Support frame, 31. Support plate, 32. Connecting rod, 4. Rolling element pin, 5. Rolling element bracket, 6. Damper, 7. Rolling element bracket mounting screw, 8. Damper nut, 9. Rolling element, 10. Mounting bracket, 11. Bracket mounting screw, 12. Rear center, 13. Gear shaft blank, 14. Support rod. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model.
[0030] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0031] In the description of this utility model, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this utility model.
[0032] The terms "first," "second," etc., used in this utility model are merely for clarity of description and are not intended to limit any order or emphasize importance. Furthermore, the term "connection" as used herein, unless otherwise specified, can refer to a direct connection or an indirect connection via other components.
[0033] Example
[0034] like Figures 1-4As shown, this embodiment provides a gear shaft rolling vibration damping fixture, including two mounting brackets 10 and two radial limiting structures. The two mounting brackets 10 are respectively connected to both sides of the rear center 12 seat; the two radial limiting structures are respectively connected to the lower end of the corresponding mounting bracket 10 and are symmetrical about the vertical line through the center of the gear shaft blank 13. The free ends of the radial limiting structures are each equipped with rolling elements 9 that can rotate along a preset axis. The rolling elements 9 roll under the drive of the gear shaft. The two rolling elements are respectively located at the lower end of the gear shaft blank 13, and the outer periphery of the rolling elements 9 is in contact with the gear shaft blank 13. The symmetrical center line of the two rolling plates 1 is on the same straight line as the rotation center of the gear shaft blank 13, thereby ensuring that the runout tolerance of the product after processing into a gear shaft is within the design range.
[0035] The rolling element in this invention is a bearing or a self-lubricating composite material bushing. The self-lubricating composite material shaft is made of PTFE (polytetrafluoroethylene) + bronze powder + carbon fiber.
[0036] See Figures 1-4 The radial limiting structure includes a support frame 3 and a damper 6. One end of the support frame 3 is connected to the mounting bracket 10, and the other end is connected to one end of the damper 6. The rolling element 9 is connected to the free end of the damper 6. By installing the damper 6 on the support frame 3 and installing the rolling element 9 on the free end of the damper 6, the damper 6 can dissipate the vibration energy generated by the gear shaft blank 13 during gear rolling through friction and viscous dissipation, thereby suppressing the radial vibration amplitude of the gear shaft blank 13. This further ensures that the runout tolerance of the product after processing into a gear shaft is within the design range. Furthermore, since the position of the damper 6 can be freely adjusted, it is convenient to meet the radial positioning of gear shaft blanks 13 with different diameters, improving the versatility of the tooling.
[0037] See Figures 1-4 The extension line of the supporting force exerted by the assembly consisting of the damper 6 and the rolling element 9 on the gear shaft blank 13 passes through the center line of the gear shaft blank 13. By passing the extension line of the supporting force through the center line of the gear shaft blank 13, the gear shaft blank 13 is subjected to force balance, further ensuring that the runout tolerance of the product after machining into a gear shaft is within the design range.
[0038] See Figures 1-4 The support frame 3 includes a connecting rod 32 and a support plate 31. The upper end of the connecting rod 32 is connected to the mounting bracket 10, and the lower end is connected to the support plate 31. The support plate 31 is inclined, and the damper 6 is mounted on the support plate 31. By inclinedly setting the support plate 31, it is convenient to make the extension line of the supporting force generated by the damper 6 and the rolling element 9 pass through the center line of the gear shaft blank 13.
[0039] See Figures 1-4The support plate 31 has a through hole, and the outer periphery of the damper 6 has an external thread. The damper 6 passes through the through hole and is screwed into the damper nut 8. This facilitates the replacement and disassembly of the damper 6.
[0040] See Figures 1-4 The radial limiting structure further includes a rolling element bracket 5, which is connected to the end of the damper 6 away from the support plate 31. The rolling element 9 is mounted on the rolling element bracket 5. By providing the rolling element bracket 5, it is easy to mount the rolling element 9 on the damper 6.
[0041] See Figure 1 and Figure 4 The rolling element support 5 is Y-shaped, and a rolling element pin 4 is installed at the open end of the rolling element support 5. The two ends of the rolling element pin 4 are respectively connected to the two side walls of the open end of the rolling element support 5. The shaft hole of the rolling element 9 is fitted onto the rolling element pin 4. By making the rolling element support 5 Y-shaped and installing the rolling element pin 4 at the open end of the rolling element support 5, it is convenient to install the rolling element 9 onto the rolling element pin 4, so that the rolling element 9 can provide radial support and limit the rotation of the gear shaft blank 13 without affecting its rotation.
[0042] See Figure 1 and Figure 4 The vertical portion of the rolling element support 5 is provided with a mounting hole that mates with the shaft hole of the damper 6. A threaded hole is provided on the side wall of the mounting hole. The rolling element support mounting screw 7, after being screwed into the threaded hole, abuts against the damper 6. This facilitates the removal of the damper 6 by disassembling the rolling element support mounting screw 7.
[0043] See Figures 1-3 The mounting bracket 10 is a long, narrow plate. It has threaded holes and connecting rod mounting holes. The connecting rod 32 has a through hole at its upper end, with one end of the connecting rod 32 containing the through hole located within the connecting rod mounting hole. A bracket mounting screw 11 passes through the through hole and engages with the threaded hole. The mounting bracket 10 and connecting rod 32 are connected by the bracket mounting screw 11 for easy disassembly and replacement.
[0044] See Figure 3It also includes two support rods 14, each support rod 14 being a long strip plate. One end of each support rod 14 is connected to the inner side of the corresponding mounting bracket 10, and the other end of each support rod 14 is provided with an inclined portion. The inclined portion is spaced apart from the outer periphery of the end of the gear shaft blank 13 away from the gear rolling plate 1. By providing two support plates 31, the end of the gear shaft blank 13 away from the gear rolling plate 1 is radially supported during operation. Under the cutting force of the gear rolling plate 1 and the supporting force of the radial limiting structure, the other end of the gear shaft blank 13 is balanced in force, preventing the gear shaft blank 13 from tilting during operation and ensuring that the runout tolerance of the product after processing into a gear shaft is within the design range.
[0045] See Figure 3 Specifically, the distance between the inclined portion and the outer periphery of the end of the gear shaft blank 13 away from the tooth rolling plate 1 is less than or equal to the runout tolerance of the gear shaft.
[0046] See Figures 1-4 The rolling element 9, rolling element pin 4, and rolling element bracket 5 are assembled. The assembled components and damper 6 are then fixed with the rolling element 9 bracket mounting screws 11. The position of the damper nut 8 is adjusted, and the damper 6 is installed on the buffer support frame 3. After the gear shaft blank 13 is placed in, the workpiece presses down the damper 6 due to its own weight. The damper 6 can absorb the weight of the workpiece itself and the energy during operation. Then, the front center 2 and the rear center 12 are pressed against the gear shaft blank 13. The upper and lower tooth rolling plates 1 squeeze the gear shaft blank 13. When the gear shaft blank 13 rotates, it drives the rolling element 9 to rotate, eliminating the wear of the damper 6. The damper 6 forms an upward thrust on the gear shaft blank 13, ensuring that during processing, the symmetrical center line of the two tooth rolling plates 1 is on the same straight line as the rotation center of the gear shaft blank 13, thereby ensuring that the runout tolerance of the product after processing into a gear shaft is within the design range.
[0047] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.
Claims
1. A gear shaft rolling vibration damping fixture, characterized in that, include: Two mounting brackets are respectively connected to both sides of the rear center seat; Two radial limiting structures are respectively connected to the lower end of the corresponding mounting bracket and are symmetrical about the vertical line through the center of the gear shaft blank. The free ends of the radial limiting structures are each equipped with a rolling element that can rotate along a preset axis. The rolling element rolls under the drive of the gear shaft. The two rolling elements are respectively located at the lower end of the gear shaft blank, and the outer periphery of the rolling element is in contact with the gear shaft blank.
2. The gear shaft rolling vibration damping fixture according to claim 1, characterized in that, The radial limiting structure includes a support frame and a damper. One end of the support frame is connected to a mounting bracket, and the other end is connected to one end of the damper. The rolling element is connected to the free end of the damper.
3. The gear shaft rolling vibration damping fixture according to claim 2, characterized in that, The extension line of the supporting force of the assembly consisting of the damper and the rolling element on the gear blank passes through the center line of the gear blank.
4. The gear shaft rolling vibration damping fixture according to claim 2, characterized in that, The support frame includes a connecting rod and a support plate. The upper end of the connecting rod is connected to the mounting bracket, and the lower end is connected to the support plate. The support plate is inclined, and the damper is installed on the support plate.
5. The gear shaft rolling vibration damping fixture according to claim 4, characterized in that, The support plate is provided with a through hole, and the outer periphery of the damper is provided with an external thread. The damper passes through the through hole and is screwed into the damper nut.
6. The gear shaft rolling vibration damping fixture according to claim 4, characterized in that, The radial limiting structure also includes a rolling element bracket, which is connected to the end of the damper away from the support plate, and the rolling element is mounted on the rolling element bracket.
7. The gear shaft rolling vibration damping fixture according to claim 6, characterized in that, The rolling element support is Y-shaped, and a rolling element pin is installed at the open end of the rolling element support. The two ends of the rolling element pin are respectively connected to the two side walls of the open end of the rolling element support, and the rolling element shaft hole is fitted into the rolling element pin.
8. The gear shaft rolling vibration damping fixture according to claim 6, characterized in that, The vertical part of the rolling element support is provided with a mounting hole that mates with the phase hole of the damper. A threaded hole is provided on the side wall of the mounting hole. After the rolling element support mounting screw is screwed into the threaded hole, it abuts against the damper.
9. The gear shaft rolling vibration damping fixture according to claim 6, characterized in that, The mounting bracket is in the shape of a long strip plate. The mounting bracket is provided with threaded holes and connecting rod mounting holes. The upper end of the connecting rod is provided with a through hole. The end of the connecting rod with the through hole is located in the connecting rod mounting hole. The bracket mounting screw passes through the through hole and engages with the threaded hole.
10. The gear shaft rolling vibration damping fixture according to any one of claims 1-9, characterized in that, It also includes two support rods, which are long strip-shaped plates. One end of each support rod is connected to the inner side of the corresponding mounting bracket, and the other end of each support rod is provided with an inclined part. The inclined part is provided with a distance from the outer periphery of the end of the gear blank away from the tooth rolling plate.