A machining fixture and machining method for a gear shaft with a flat structure on the shaft side

Abstract

The present invention belongs to the technical field of precision parts processing, and provides a processing fixture and processing method for a gear shaft with a flat structure on the shaft side, which mainly includes a first mounting plate and a second mounting plate, wherein a plurality of processing grooves are arranged side by side on the first mounting plate, and the plurality of processing grooves are arranged close to the first side of the first mounting plate; the cross-sectional dimensions of the processing grooves are matched with the cross-sectional dimensions of the shaft body, and the distance from the axis of the plurality of processing grooves arranged side by side to the first side is smaller than the radius of the shaft body, and along the normal direction of the first side, the depth of the processing grooves is greater than the radius of the shaft body; a plurality of positioning holes for the gears of the gear shaft to extend into are arranged coaxially on the second mounting plate corresponding to the processing grooves, and a toothed structure is arranged in the positioning hole, and the toothed structure is matched with the gears. The present invention can improve the processing efficiency and processing quality of the gear shaft while effectively reducing the production cost.

Description

Technical Field

[0001] The invention belongs to the technical field of precision parts processing, and in particular relates to a processing fixture and a processing method for a gear shaft with a flat structure on the shaft side. Background Art

[0002] Precision flat and grooved gear shafts are indispensable parts in the hinge mechanism used in various brands of folding screen mobile phones. The hinge mechanism relies on this core part to achieve rotation. With the continuous development and iteration of folding screen mobile phones of various brands, the demand for this type of gear shaft is also increasing. However, the processing of this type of gear shaft requires high precision, especially the strict angle size control between the flat plane and the tooth shape. This structure is difficult to achieve with general traditional precision processing technology.

[0003] At present, the existing feasible method is mainly to process through CNC turning and milling composite processing equipment. Although this processing method can achieve one-time clamping and forming, it has a good basis for geometric tolerance control. However, the price of CNC turning and milling composite processing equipment with high precision requirements is very expensive, so enterprises must bear extremely high investment costs and equipment depreciation losses; moreover, since the gears need to be milled tooth by tooth at this time, the dimensional accuracy requirements of the tool will be further increased, and the efficiency of tooth by tooth processing is low, and the tool often wears. The tooth profile accuracy processed in this form can only reach 6-7 levels, and the wear of the tool will cause uneven tooth profile, which makes the hinge mechanism of the gear shaft not smooth and stable enough when it is actually put into use, and there are even jams and abnormal noises. Summary of the invention

[0004] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a processing fixture and a processing method for a gear shaft with a flat structure on the side of the shaft, so that the processing of the precision gear shaft with flat and groove structures can effectively reduce the production cost while improving the processing efficiency and processing quality of the gear shaft.

[0005] The technical solution adopted by the present invention to solve the technical problem is:

[0006] A machining fixture for a gear shaft with a flat structure on the shaft side, comprising:

[0007] A first mounting plate, wherein a plurality of machining grooves are arranged side by side on the first mounting plate for the shaft body of the gear shaft to extend into, and the plurality of machining grooves are arranged close to the first side surface of the first mounting plate; the cross-sectional dimensions of the machining grooves match the cross-sectional dimensions of the shaft body, and the distances from the axis centers of the plurality of machining grooves arranged side by side to the first side surface are smaller than the radius of the shaft body, and along the normal direction of the first side surface, the depths of the machining grooves are greater than the radius of the shaft body;

[0008] A second mounting plate, wherein a plurality of positioning holes for the gears of the gear shaft to extend into are coaxially arranged on the second mounting plate corresponding to the processing groove, and a toothed structure is arranged in the positioning hole, and the toothed structure is adapted to the gears.

[0009] Preferably, the second mounting plate is further provided with a plurality of first mounting holes for detachable mounting with the first mounting plate.

[0010] Preferably, the plurality of first mounting holes are symmetrically arranged with the straight line where the axes of the plurality of positioning holes are located as the center.

[0011] Preferably, the positioning holes are provided with limit blocks correspondingly to each other for preventing the gear shaft from moving axially.

[0012] Preferably, a base is further included, and the first mounting plate or the second mounting plate is further provided with a plurality of second mounting holes for detachable mounting with the base.

[0013] A method for processing a gear shaft with a flattened structure on the shaft side, comprising the following steps:

[0014] S10. Taking the raw material for turning to form a gear shaft blank;

[0015] S20. Processing the gear shaft blank for gear;

[0016] S30. Based on the machining fixture for a gear shaft with a flat structure on the shaft side, the shaft body of the gear shaft after gear machining is inserted into the machining groove, and the gear of the gear shaft is inserted into the positioning hole. After installation and fixing, the flat structure of the gear shaft is milled through the first side surface;

[0017] S40. Obtain several finished gear shafts that meet the size requirements.

[0018] Furthermore, in step S20, when the gear shaft blank is subjected to gear processing, the gear of the gear shaft is formed by gear hobbing.

[0019] Furthermore, the tooth-shaped structure in the positioning hole is formed by wire cutting.

[0020] Furthermore, in step S30, after the flat structure on one side of the gear shaft is milled, the installation state between the gear of the gear shaft and the tooth structure is maintained, and after the shaft body of the gear shaft is pulled out of the processing groove, the second mounting plate is flipped 180° in the horizontal direction, and then the shaft body of the gear shaft is correspondingly extended into the processing groove to perform milling of the flat structure on the other side.

[0021] Furthermore, when the flat structure is milled, if there is a slot structure on the flat structure, the flat structure and the slot structure are milled sequentially in the same process.

[0022] Compared with the prior art, the beneficial effects of the present invention include:

[0023] In this solution, a first mounting plate and a second mounting plate are provided, and a processing groove is cleverly provided on the first mounting plate. The processing groove can expose the portion of the gear shaft body on which the flat structure needs to be processed and set outside the first side surface for easy milling processing; in addition, a positioning hole is provided on the second mounting plate, and a tooth structure that is compatible with the gear of the gear shaft is cleverly provided in the positioning hole. The gear shaft is clamped and fixed between the first mounting plate and the second mounting plate, which effectively solves the problem in the prior art that after the gear is formed by the gear hobbing process, it is impossible to use CNC equipment to process the flat structure with strict angle requirements on the tooth shape. The production of the gear shaft can be mass-produced, which greatly improves the production efficiency. Moreover, the tooth shape processing accuracy of the gear can be effectively controlled under the premise of ensuring that the angle requirements are met.

[0024] In addition, by using this solution, the high cost problem directly caused by the use of turning and milling composite CNC equipment on traditional technology can be effectively avoided, greatly reducing the company's operating risks; at the same time, when processing gears alone, since it is not limited by the characteristics of the equipment, the optional methods are more flexible. For example, when using the gear hobbing method, the service life of its tool is much longer than that of the tool using the turning and milling composite CNC equipment, which has a higher guarantee for the tooth shape accuracy and reduces the tool investment cost. In addition, the entire fixture is simple to operate, and the processing efficiency is still ensured or even improved on the basis of realizing process separation, which can bring better economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0026] Figure 1 It is a schematic diagram of the installation structure of the present invention.

[0027] Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention.

[0028] Figure 3 It is a schematic diagram of the side structure of the positioning hole of the present invention.

[0029] Figure 4It is a schematic structural diagram of the gear shaft of the present invention.

[0030] in:

[0031] 1-first mounting plate, 11-processing groove, 12-first side surface, 13-first bolt, 131-first nut, 14-second mounting hole;

[0032] 2-second mounting plate, 21-positioning hole, 211-toothed structure, 212-limiting block, 22-first mounting hole;

[0033] 3-gear shaft, 31-shaft body, 32-gear, 33-flat structure;

[0034] 4-base, 41-second bolt, 411-second nut. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. In the following description, many specific details are set forth in order to fully understand the present invention, and the embodiments described are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the art without making creative work are within the scope of protection of the present invention.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0037] Example 1

[0038] like Figure 1-4 As shown, in this embodiment, a processing fixture for a gear shaft with a flat structure on the side of the shaft is provided, which mainly includes a first mounting plate 1 and a second mounting plate 2. The gear shaft 3 is provided with a shaft body 31 and a gear 32 arranged on the shaft body 31.

[0039] Specifically, the first mounting plate 1 is provided with a plurality of machining grooves 11 arranged side by side in an "I" shape at intervals, and the cross-sectional dimensions of the machining grooves 11 are adapted to the cross-sectional dimensions of the shaft body 31, so that the shaft body 31 can be inserted into the machining grooves 11 and form radial positioning; wherein, a plurality of the machining grooves 11 are arranged close to the first side surface 12 of the first mounting plate 1, and the distance from the axis center of a plurality of the machining grooves 11 arranged side by side to the first side surface 12 is smaller than the radius of the shaft body 31, so that when the shaft body 31 is installed in the machining grooves 11, part of the shaft body 31 will be exposed outside the first side surface 12, thereby facilitating the milling of the flat structure 33; and along the normal direction of the first side surface 12, the depth of the machining grooves 11 is greater than the radius of the shaft body 31, so that the effective contact arc length between the shaft body 31 and the machining grooves 11 is greater than the semicircular circumference of the shaft body 31, thereby effectively realizing the radial limitation of the shaft body 31.

[0040] In addition, a plurality of positioning holes 21 are provided on the second mounting plate 2 corresponding to the processing groove 11, and a plurality of the positioning holes 21 are coaxially arranged with the processing groove 11, and the positioning holes 21 are provided for the gear 32 of the gear shaft 3 to extend into and be arranged; wherein, a toothed structure 211 is provided in the positioning hole 21, and the toothed structure 211 is adapted to the gear 32; so that when the toothed structure 211 is processed and designed, it can be processed according to the angular relationship between the tooth shape of the gear 32 and the flat structure 33, so that when the shaft body 31 of the gear shaft 3 installed in the positioning hole 21 is milled, the flat structure 33 obtained by milling can easily reach the required angular relationship, and the installation and positioning are convenient and the reliability is strong.

[0041] The second mounting plate 2 is also provided with a plurality of first mounting holes 22 for detachable mounting with the first mounting plate 1, so that when the second mounting plate 2 or the first mounting plate 1 is replaced, the flat structure 33 of the gear shaft 3 with the same shaft body 31 size and different gear 32 tooth shape or the shaft body 31 size and the same gear 32 tooth shape can be processed, and the deployment is more convenient and flexible. At the same time, a plurality of first bolts 13 are provided on the first mounting plate 1 corresponding to the first mounting holes 22, and first nuts 131 are provided corresponding to the first bolts 13.

[0042] As a preferred solution, one end of the first bolt 13 is embedded or set in the first mounting plate 1, and the other end of the first bolt 13 is set toward the second mounting plate 2. In the installed state, the first bolt 13 is correspondingly inserted into the first mounting hole 22, and the first nut 131 is tightened on the first bolt 13 to achieve the fastening installation between the first mounting plate 1 and the second mounting plate 2. At this time, the first mounting plate 1 can be fixedly installed on the workbench of the CNC equipment, or the second mounting plate 2 can be fixedly installed on the workbench of the CNC equipment; considering the force stability during processing, in this embodiment, it is preferred to fix the first mounting plate 1 on the workbench of the CNC equipment.

[0043] Furthermore, a plurality of the first mounting holes 22 are symmetrically arranged with the straight line where the axes of the plurality of the positioning holes 21 are located as the center, so that after the shaft body 31 is pulled out of the processing groove 11, the gear shaft 3 installed in the positioning hole 21 of the second mounting plate 2 can remain in the installed state, and as the second mounting plate 2 is flipped 180° on the horizontal plane, it can be re-extended into the processing groove 11, thereby performing milling processing on the flat structure 33 on the other side, effectively avoiding secondary disassembly and installation of the gear shaft 3, and further avoiding processing errors caused by multiple clamping.

[0044] As a preferred solution, the first mounting holes 22 can be diagonally arranged on the diagonal lines of several of the positioning holes 21 to facilitate the fastening and installation of the second mounting plate 2 and the installation after flipping; as another preferred solution, in this embodiment, the first mounting holes 22 are arranged in a matrix on the second mounting plate 2, so that when in the installed state, the first mounting holes 22 in use can be located on the same side of several of the positioning holes 21, thereby avoiding the first mounting plate 1 having to make corresponding structural adjustments when the first mounting holes 22 are set in a diagonal form, which may affect the tool during milling.

[0045] The positioning holes 21 are also provided with stop blocks 212 for preventing the gear shaft 3 from moving axially. The stop blocks 212 and the processing grooves 11 are used to limit the gear shaft 3 in radial and axial directions, ensuring a stable processing state. As a preferred solution, in this embodiment, the stop blocks 212 are provided in the form of pins to be fixedly provided in the positioning holes 21, and the axial limitation of the gear shaft 3 is achieved by adjusting the fastening relationship between the first nut 131 and the first bolt 13. In actual use, it is also possible to consider providing the stop blocks 212 and the second mounting plate 2 as an integrated structure.

[0046] Furthermore, in this embodiment, a base 4 is also provided, and the first mounting plate 1 or the second mounting plate 2 is also provided with a plurality of second mounting holes 14 for detachable installation with the base 4. The base 4 is provided to facilitate the adaptation and installation of the entire processing fixture and the work surface of the CNC equipment. As a preferred solution, in this embodiment, the second mounting hole 14 is provided on the first mounting plate 1, so that the first mounting plate 1 and the base 4 are fitted from top to bottom, and the force is more stable and reliable in the milling state. In addition, a plurality of second bolts 41 and second nuts 411 provided to match the second bolts 41 are provided on the base 4, one end of the second bolt 41 is pre-embedded or set on the base 4, and the other end of the second bolt 41 is extended toward the first mounting plate 1. In the installed state, the second bolt 41 is passed through the second mounting hole 14 and is tightened and fixed by the second nut 411.

[0047] In order to facilitate further understanding of the present solution, a method for processing a gear shaft with a flat structure on the shaft side is also provided in the present embodiment, which mainly includes the following steps:

[0048] S10. Taking the bar raw material for turning to form a gear shaft blank;

[0049] S20. Process the gear shaft blank for gear processing; wherein, when processing the gear shaft blank for gear processing, the gear 32 of the gear shaft 3 is formed by gear hobbing. Precision gear hobbing equipment is cheaper than CNC turning and milling equipment. At the same time, compared with the traditional technology of tooth-by-tooth milling, gear hobbing can reduce the processing time by 70%, so that the processing efficiency of the entire part can be improved by 50%; in addition, for the tool investment cost, the hob used in the gear hobbing process has an average service life of 80,000 to 100,000 parts for the processing of gear shafts of the same specification; while the average life of the tool in the turning and milling CNC equipment is only 700 to 1,000 parts; therefore, in mass production, the use of gear hobbing can save 60% of the tool cost. The gear hobbing process has been used in automatic mechanical watches, and the gear hobbing accuracy can reach 4-5 levels, which is higher than the traditional compound milling process.

[0050] Furthermore, the toothed structure 211 in the positioning hole 21 is formed by wire cutting, and the processing accuracy is more controllable, and the production of one second mounting plate 2 can be suitable for the installation and use of multiple and multiple batches of gear shafts 3. Through the precise fit between the inner contour of the toothed structure 211 and the gear 32 of the gear shaft 3, a precise angle is formed between the flat plane of the post-milling flat structure 33 and the toothed shape, thereby effectively ensuring the use of the gear shaft 3 in the hinge mechanism.

[0051] S30. Based on the above-mentioned machining fixture for a gear shaft with a flat structure on the shaft side, the shaft body 31 of the gear shaft 3 after gear machining is extended into the machining groove 11, and the gear 32 of the gear shaft 3 is extended into the positioning hole 21. After installation and fixation, the flat structure 33 of the gear shaft 3 is milled through the first side surface 12.

[0052] After the flat structure 33 on one side of the gear shaft 3 is milled, the installation state between the gear 32 of the gear shaft 3 and the tooth structure 211 is maintained, and after the shaft body 31 of the gear shaft 3 is pulled out of the processing groove 11, the second mounting plate 2 is flipped 180° in the horizontal direction, and then the shaft body 31 of the gear shaft 3 is correspondingly extended into the processing groove 11 to perform milling of the flat structure 33 on the other side.

[0053] Furthermore, when the flat structure 33 is milled, if there is a slot structure on the flat structure 33, the flat structure 33 and the slot structure are milled sequentially in the same process.

[0054] S40. Obtain several finished gear shafts 3 that meet the size requirements.

[0055] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Therefore, any modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for processing a gear shaft with a flattened structure on the shaft side, characterized in that: A processing fixture for a gear shaft with a flat structure on the shaft side is provided, and the processing fixture comprises: A first mounting plate, wherein a plurality of machining grooves are arranged side by side on the first mounting plate for the shaft body of the gear shaft to extend into, and the plurality of machining grooves are arranged close to the first side surface of the first mounting plate; the cross-sectional dimensions of the machining grooves match the cross-sectional dimensions of the shaft body, and the distances from the axis centers of the plurality of machining grooves arranged side by side to the first side surface are smaller than the radius of the shaft body, and along the normal direction of the first side surface, the depths of the machining grooves are greater than the radius of the shaft body; A second mounting plate, wherein a plurality of positioning holes for the gears of the gear shaft to extend into are coaxially arranged on the second mounting plate corresponding to the processing groove, and a tooth-shaped structure is arranged in the positioning hole, and the tooth-shaped structure is adapted to the gear; The second mounting plate is also provided with a plurality of first mounting holes for detachable mounting with the first mounting plate; The plurality of first mounting holes are symmetrically arranged with the straight line where the axes of the plurality of positioning holes are located as the center; The processing method comprises the following steps: S10. Taking the raw material for turning to form a gear shaft blank; S20. Gear processing of the gear shaft blank; S30. Based on the machining fixture of the gear shaft with a flat structure on the shaft side, the shaft body of the gear shaft after gear machining is inserted into the machining groove, and the gear of the gear shaft is inserted into the positioning hole. After installation and fixing, the flat structure of the gear shaft is milled through the first side surface; After the flat structure on one side of the gear shaft is milled, the gear of the gear shaft and the toothed structure are kept installed, the shaft body of the gear shaft is pulled out of the processing groove, the second mounting plate is flipped 180 degrees in the horizontal direction, and the shaft body of the gear shaft is correspondingly inserted into the processing groove to perform milling of the flat structure on the other side; When the flat structure is milled, if there is a slot structure on the flat structure, the flat structure and the slot structure are milled sequentially in the same process; S40. Obtain several finished gear shafts that meet the size requirements.

2. The method for processing a gear shaft with a flattened structure on the shaft side according to claim 1, characterized in that: The positioning holes are provided with limit blocks correspondingly to each other for preventing the gear shaft from moving axially.

3. The method for processing a gear shaft with a flattened structure on the shaft side according to any one of claims 1 to 2, characterized in that: The processing fixture for the gear shaft with a flat structure on the shaft side also includes a base, and the first mounting plate or the second mounting plate is also provided with a plurality of second mounting holes for detachable mounting with the base.

4. The method for processing a gear shaft with a flattened structure on the shaft side according to claim 1, characterized in that: In step S20, when the gear shaft blank is subjected to gear processing, the gear of the gear shaft is formed by gear hobbing.

5. The method for processing a gear shaft with a flattened structure on the shaft side according to claim 1, characterized in that: The tooth-shaped structure in the positioning hole is formed by wire cutting.

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