A tool for processing a double gear shaft with different diameters and a processing method

Abstract

The present application relates to the field of tooling structure design, especially to a tooling and machining method for machining a double gear shaft with different diameters. When the gears of the double gear shaft are machined, a great reverse force will be generated, which will cause the gear surface to warp and deform or even cause more serious cross-section phenomenon. The purpose of the present application is to provide a tooling and machining method for machining a double gear shaft with different diameters. Through the tooling and machining method for machining a double gear shaft with different diameters, the pre-tightening force of the end faces of the tooling on the inner end faces of the double gears of the double gear shaft is used to ensure that there is no gap between the tooling and the parts when the tooling is supported, so as to ensure the machining precision and the qualified rate, and the gear machining precision is IT6-IT7. The double gear spacing can be supported, and flexible adjustment can be made according to different double gear spacings, and the structure is simple.

Description

Technical Field

[0001] This invention relates to the field of tooling structure design, and in particular to a tooling and machining method for machining double gear shafts of different diameters. Background Technology

[0002] The gears in a double-gear shaft generate significant reverse forces during machining, which can lead to warping or even more severe cross-sectional deformation of the gear surface. Traditionally, the machining of the two gears in a double-gear shaft is achieved using gear hobbing or gear shaping. However, these methods, such as the ratio of the gear's outer diameter to the shaft's diameter and the distance between the two gears, reduce the shaft's rigidity, causing vibration during machining and affecting both machining accuracy and efficiency. Furthermore, the gear thickness further reduces the rigidity of the tooth end faces, impacting machining accuracy and efficiency. It should be noted that the difference between a double gear and a double gear shaft is that a double gear has a through hole and two gears, while a double gear shaft has a shaft and two gears. Summary of the Invention

[0003] The purpose of this invention is to provide a tooling and processing method for machining a double gear shaft with different diameters, which can support the distance between the two gears, flexibly adjust the distance between the two gears according to different distances, and has a simple structure.

[0004] This invention proposes a tooling for machining a double-gear shaft with different diameters. The tooling includes an external clamping structure and an internal support structure. The external clamping structure includes a locking cover, a support stud, a flange, and a nut. The support stud has a turning rod in the middle. The lower threaded rod at the lower end of the turning rod passes through the flange and is locked by the nut. The upper threaded rod at the upper end of the turning rod engages with the locking cover to lock the larger diameter disc. The smaller diameter disc extends upwards beyond the bottom surface of the locking cover. The internal support structure includes an upper support block and a lower support block. The upper support block includes an upper support head and a hollow threaded rod, and has a shaft positioning hole and an upper opening groove. The lower support block has a second threaded hole and a lower opening groove. The hollow threaded rod engages with the second threaded hole. When the upper and lower opening grooves are aligned, it is inserted into the shaft between the larger and smaller diameter discs. The larger and smaller diameter discs are supported by adjusting the distance between the upper and lower support blocks.

[0005] Advantageously, the outer circle of the locking cover has knurling, the interior has a first threaded hole, and the bottom of the cover has a through hole whose diameter can pass through a small-diameter disc but cannot pass through a large-diameter disc.

[0006] Advantageously, the upper support head is supported by the outer end face of the inner end face of the small-diameter disk, and the annular surface of the upper support head has an upper parallel surface for operation.

[0007] Advantageously, the annular surface of the lower support block has a lower parallel surface for operation, and the outer end face of the lower support block supports the inner end face of the large-diameter disk.

[0008] Advantageously, the end face of the upper threaded rod of the support stud is a positioning surface, and a shaft end positioning hole is located at the center of the positioning surface to position the outer end shaft of the large-diameter disk.

[0009] Advantageously, a pin hole is provided at the eccentric position of the positioning surface, one end of the positioning pin is inserted into the pin hole, and the other end is locked in the large-diameter disk for limiting in the machined teeth.

[0010] Advantageously, the turning rod has a parallel surface for operation.

[0011] Advantageously, the upper end face of the flange is in contact with the lower end face of the screwing rod, and the flange has evenly distributed radial long slots through which screws are passed and tightened onto the gear hobbing machine.

[0012] This invention also proposes a method for machining a double gear shaft with different diameters. When machining the teeth of a large-diameter disk using the above-mentioned tooling, the method includes the following steps: S1. Using the internal support structure, the hollow threaded rod is screwed into the second threaded hole, and after the upper opening groove and the opening groove are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk. S2. Adjust the spacing between the upper and lower support blocks to ensure they are close enough to support the large-diameter and small-diameter discs; S3. During gear shaping, the outer end shaft of the small diameter disc is clamped on the three-jaw chuck fixture of the gear shaping machine, and the gear shaping machine is started to perform gear shaping on the large diameter disc; during gear hobbing, the outer end shaft of the small diameter disc is clamped on one end of the gear hobbing machine, and the outer end shaft of the large diameter disc is clamped on the other end of the gear hobbing machine to perform gear hobbing.

[0013] This invention also proposes a method for machining a double gear shaft with different diameters, using the aforementioned tooling. When machining the teeth of a small-diameter disk using gear hobbing, the following steps are included: S1. Insert the threaded rod into the flange and tighten it with a nut; install the flange on the gear hobbing machine and tighten it. S2. Using the internal support structure, screw the hollow threaded rod into the second threaded hole, align the upper opening groove and the opening groove, and then insert it into the shaft between the large diameter disk and the small diameter disk. S3. Adjust the spacing between the upper and lower support blocks to ensure they are close enough to support the large-diameter and small-diameter discs; S4. Press the locking cover firmly onto the end face of the large-diameter disc and tighten it; S5. Start the gear shaping machine to perform gear shaping on the small-diameter disc; The following steps are included when hobbing the teeth of a pinion: S1. Using the internal support structure, the hollow threaded rod is screwed into the second threaded hole, and after the upper opening groove and the opening groove are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk. S2. Adjust the spacing between the upper and lower support blocks to ensure they are close enough to support the large-diameter and small-diameter discs; S3. Clamp the outer end shaft of the large diameter disc at one end of the gear hobbing machine, and clamp the outer end shaft of the small diameter disc at the other end of the gear hobbing machine. S4: Start the gear hobbing machine to perform gear hobbing on the small gear of the part.

[0014] Beneficial effects: Through the tooling and processing method for machining the differential diameter double gear shaft of the present invention, the preload force of the tooling end faces on the inner end faces of the double gears of the gear shaft is applied to the end faces of the tooling end faces, so that there is no gap between the tooling and the part when the tooling is supported, thus ensuring the machining accuracy and pass rate. The gear machining accuracy is IT6-IT7.

[0015] It can support double gear shafts with different tooth pitches, solving the deformation and cross-section problems when machining gears and milling heavy holes on double gear shafts. Attached Figure Description

[0016] Figure 1 This is a three-dimensional diagram of the tooling structure for machining the differential diameter double gear shaft of the present invention; Figure 2 This is an exploded view of the tooling structure for machining the differential diameter double gear shaft of the present invention; Figure 3 This is a schematic diagram of the locking cover structure; Figure 4 This is a schematic diagram of the upper support block; Figure 5 This is a schematic diagram of the lower support block. Figure 6 This is a schematic diagram of the supporting stud. Figure 7 This is a schematic diagram of the flange structure.

[0017] 1—Locking cover, 2—Upper support block, 3—Lower support block, 4—Positioning pin, 5—Support stud, 6—Flange, 7—Nut, N—Part, 11—Knurled, 12—Through hole, 121—Bottom surface of cover, 13—First threaded hole, 21—Upper opening groove, 22—Shaft positioning hole, 23—Upper support head, 24—Upper parallel surface, 25—Hollow threaded rod, 31—Lower opening groove, 32—Second threaded hole, 33—Lower parallel surface, 34—Outer end face, 51—Shaft end positioning hole, 52—Positioning surface, 53—Pin hole, 54—Upper threaded rod, 55—Tightening rod, 56—Lower end face, 57—Lower threaded rod, 61—Upper end face, 62—Through hole, 63—Radial long groove, 64—Lower end face Detailed Implementation See Figure 1and Figure 2 The tooling structure shown is used for machining a double gear shaft with different diameters. The tooling includes an external clamping structure and an internal support structure, and mainly consists of 7 parts: locking cover 1, upper support block 2, lower support block 3, locating pin 4, support stud 5, flange 6, and nut 7.

[0018] See Figure 3 The locking cover 1 shown has knurled edges 11 on its outer circumference, which increases the friction when tightening by the operator's hand, making operation easier. The bottom of the locking cover 1 has a through hole 12, which allows a small-diameter disc of the workpiece blank to pass through, but not a large-diameter disc. The bottom surface 121 of the locking cover 1 is in contact with the end face of the large-diameter disc. The locking cover 1 includes a first threaded hole 13, which is screwed onto the upper threaded rod 54 of the support stud 5, so that the bottom surface 121 of the cover presses against the end face of the large-diameter disc, wherein the bottom surface 121 of the cover is perpendicular to the first threaded hole 13.

[0019] See Figure 4 The upper support block 2 shown has a shaft positioning hole 22, and includes a hollow threaded rod 25 and an upper support head 23, both of which have an upper opening groove 21. The upper support block 2 is inserted into the shaft between the large-diameter and small-diameter discs, and the shaft positioning hole 22 positions the shaft. The outer end face of the upper support head 23 supports the inner end face of the small-diameter disc. The annular surface of the upper support head 23 has an upper parallel surface 24, which facilitates the operator to rotate the upper support block 2 with a wrench. The hollow threaded rod 25 engages with the second threaded hole 32 of the lower support block 3, allowing the upper support block 2 to move freely along the axial direction, thus adjusting and supporting the blanks of double gear shaft parts with different spacings.

[0020] See Figure 5 The lower support block 3 shown has a second threaded hole 32 inside. The annular surface of the lower support block 3 has a lower parallel surface 33, and the lower support block 3 has a lower opening groove 31. Through this lower opening groove 31, the lower support block 3 can be inserted into the shaft between the large-diameter and small-diameter disks without interference. The aforementioned second threaded hole 32 cooperates with the hollow threaded rod 25, allowing the upper support block 2 to move freely axially, enabling adjustment and support of double-gear parts with different spacings. The lower parallel surface 33 facilitates the operator's use of a wrench to fix the lower support block 3. The outer end face 34 of the lower support block 3 supports the inner end face of the large-diameter disk.

[0021] See Figure 6The support stud 5 shown includes an integral upper threaded rod 54, a tightening rod 55, and a lower threaded rod 57. The upper threaded rod 54 has a shaft end positioning hole 51 at the center of the positioning surface 52 and a pin hole 53 at an eccentric position on the positioning surface 52. One end of the part blank is inserted into the shaft end positioning hole 51, which provides high positioning accuracy in the radial direction of the part. The shaft end positioning hole 51 is perpendicular to the positioning surface 52. The positioning surface 52 is in contact with the outer end face of the large-diameter disk, which provides high positioning accuracy in the axial direction of the part. The shaft end positioning hole 51 is perpendicular to the positioning surface 52. A positioning pin 4 is inserted into the pin hole 53. The exposed part of the positioning pin 4 is locked in the teeth of the large-diameter disk for limiting the movement of the part in the radial direction during processing. The pin hole 53 is perpendicular to the positioning surface 52. The tightening rod 55 has a parallel surface, which facilitates the operator to use a wrench to fix the support stud 5. The lower end face 56 of the screw rod 55 is positioned against the upper end face 61 of the flange 6, with the lower end face 56 parallel to the positioning surface 52. The threaded rod 57 passes through the through hole 62 of the flange 6 and is tightened with the nut 7 to secure the flange 6.

[0022] Since gears are mainly subjected to large axial forces and relatively small radial forces during machining, the pin holes 53 of the locating pin 4 and the support stud 5 can be added or removed depending on the machining requirements.

[0023] See Figure 7 The flange 6 shown has its upper end face 61 abutting against the lower end face 56 of the support stud 5, wherein the upper end face 61 is parallel to the lower end face 64 and perpendicular to the through hole 62. After the lower screw 57 of the support stud 5 passes through the through hole 62, the lower end face 56 of the screw rod 55 is tightened to fit against the upper end face 61 of the flange 6, and then the lower end face 64 of the flange 6 is locked by the nut 7, thus completing the fastening of the support stud 5, the flange 6, and the nut 7. The flange 6 has evenly distributed radial grooves 63. In this embodiment, the flange 6 includes three evenly distributed radial grooves 63. Screws are passed through the grooves 63 and tightened onto the gear hobbing machine, thus completing the fastening of the flange 6 on the gear hobbing machine.

[0024] For the blank of the double gear shaft, the large gear and small gear have been precision machined according to the outer diameter of the gears. Then, the large gear and small gear are machined using a double gear shaft machining fixture. When using the double gear shaft machining fixture of this invention, for applications in gear shaping and gear hobbing, the following four machining processes are included in combination: 1. Large gear hobbing + small gear hobbing; 2. Large gear hobbing + small gear shaping; 3. Large gear shaping + small gear shaping; 4. Large gear shaping + small gear hobbing.

[0025] When selecting machining processes for dual gear parts, the preferred method is hobbing the large gear followed by hobbing the small gear. This method offers high precision, high efficiency, and is more convenient to operate. Hobbing can achieve a maximum tooth precision grade of IT6, while gear shaping can achieve a maximum tooth precision grade of IT7. If equipment limitations or part structure constraints prevent the selection of other machining methods, then the remaining three machining methods can be chosen.

[0026] Large gear machining 1. Gear shaping for large gears S1: Screw the hollow threaded rod 25 of the upper support block 2 into the second threaded hole 32 of the lower support block 3, so that the upper opening groove 21 and the opening groove 31 are aligned, and at the same time make the distance between the upper support head 23 and the outer end face 34 less than the distance between the inner end faces of the large diameter disk and the small diameter disk. Then insert the assembled tooling body into the shaft of the part for positioning. S2: After using a wrench to fix the lower parallel surface 33 of the lower support block 3, another wrench is used to rotate the upper parallel surface 24 of the upper support block 2 clockwise, which increases the distance between the upper support head 23 and the outer end face 34. The upper support head 23 is in contact with the inner end face of the small diameter disc and there is a preload, and the outer end face 34 is in contact with the inner end face of the large diameter disc and there is a preload. S3: Clamp the outer end shaft of the small diameter disc onto the three-jaw chuck fixture of the gear shaper; S4: Start the gear shaping machine to perform gear shaping on the large-diameter disc; S5: After the part is processed, the gear shaper stops, the three-jaw chuck of the gear shaper is loosened, and the part with the tightened upper support block 2 and lower support block 3 is taken out.

[0027] S6: Use a wrench to remove the upper support block 2 and the lower support block 3 from the part. The large gear of the part is now machined. 2. Gear hobbing of large gears S1: Screw the hollow threaded rod 25 of the upper support block 2 into the second threaded hole 32 of the lower support block 3, so that the upper opening groove 21 and the opening groove 31 are aligned, and at the same time make the distance between the upper support head 23 and the outer end face 34 less than the distance between the inner end faces of the large diameter disk and the small diameter disk. Then insert the assembled tooling body into the shaft for positioning. S2: After using a wrench to fix the lower parallel surface 33 of the lower support block 3, another wrench is used to rotate the upper parallel surface 24 of the upper support block 2 clockwise, which increases the distance between the upper support head 23 and the outer end face 34. The upper support head 23 is in contact with the inner end face of the small diameter disc and there is a preload, and the outer end face 34 is in contact with the inner end face of the large diameter disc and there is a preload. S3: The outer end shaft of the small diameter disc is clamped on one end of the gear hobbing machine, and the outer end shaft of the large diameter disc is clamped on the other end of the gear hobbing machine in a clamping and lifting manner. S4: Start the gear hobbing machine to perform gear hobbing on the large gear of the part; S5: After the part is processed, the gear hobbing machine stops, the tooling of the gear hobbing machine is loosened, and the part with the tightened upper support block 2 and lower support block 3 is taken out.

[0028] S6: Use a wrench to remove the upper support block 2 and the lower support block 3 from the part. The large gear of the part is now machined. S7: Remove burrs from parts during gear hobbing.

[0029] S8: Warehousing - After the parts are processed, they are oiled and put into storage.

[0030] Small gear machining 1. Gear shaping S1: After inserting the lower threaded rod 57 of the support stud 5 into the flange 6, tighten it with the nut 7; install the flange 6 on the gear hobbing machine and tighten it with screws through the radial long groove 63; S2: Screw the hollow threaded rod 25 of the upper support block 2 into the second threaded hole 32 of the lower support block 3, so that the upper opening groove 21 and the lower opening groove 31 are aligned, and the distance between the upper end face of the upper support head 23 and the outer support surface 34 of the lower support block 3 is less than the distance between the inner end faces of the double gear of the part. Then insert the assembled tooling body between the large diameter disk and the small diameter disk, and use the shaft positioning hole 22 to position the shaft. S3: After fixing the lower parallel surface 33 of the lower support block 3 with a wrench, rotate the upper parallel surface 24 of the upper support block 2 with another wrench to increase the distance between the upper support head 23 and the outer end face 34. The upper support head 23 is in contact with the inner end face of the small diameter disc and there is a preload, and the outer end face 34 is in contact with the inner end face of the large diameter disc and there is a preload. S4: Insert the outer end shaft of the large diameter disc into the shaft end positioning hole 51 of the support stud 5. Use the positioning pin 4 according to the processing requirements. If the teeth of the large diameter disc have been processed, then a single tooth is stuck on the positioning pin 4. S5: Press the bottom surface 121 of the locking cover 1 against the end face of the large diameter disc, and the operator tightens the knurled part 11 of the locking cover 1 by hand. S6: Start the gear shaping machine to perform gear shaping on the small-diameter disc; S7: After the part is processed, the gear hobbing machine stops, the locking cover 1 is loosened, and the part with the tightening upper support block 2 and lower support block 3 is taken out; S8: Use a wrench to remove the upper support block 2 and the lower support block 3 from the part. The small gear is now machined.

[0031] 2. Gear hobbing of pinions S1: Screw the hollow threaded rod 25 of the upper support block 2 into the second threaded hole 32 of the lower support block 3, so that the upper opening groove 21 and the opening groove 31 are aligned, and at the same time make the distance between the upper support head 23 and the outer end face 34 less than the distance between the inner end faces of the large diameter disk and the small diameter disk. Then insert the assembled tooling into the shaft so that the shaft positioning hole 22 positions the shaft. S2: After using a wrench to fix the lower parallel surface 33 of the lower support block 3, another wrench rotates the upper parallel surface 24 of the upper support block 2, which increases the distance between the upper support head 23 and the outer end face 34. The upper support head 23 is in contact with the inner end face of the small diameter disc and there is a pre-tightening force, and the outer end face 34 is in contact with the inner end face of the large diameter part and there is a pre-tightening force. S3: The outer end shaft of the large diameter disc is clamped on one end of the gear hobbing machine, and the outer end shaft of the small diameter disc is clamped on the other end of the gear hobbing machine. This is a clamping and lifting method. S4: Start the gear hobbing machine to perform gear hobbing on the small gear of the part; S5: After the part is processed, the gear hobbing machine stops, the tooling of the gear hobbing machine is loosened, and the part with the tightened upper support block 2 and lower support block 3 is taken out. S6: Use a wrench to remove the upper support block 2 and the lower support block 3 from the part. The small gear of the part is now machined.

Claims

1. A tooling for machining a double gear shaft with different diameters, characterized in that: The tooling includes an external clamping structure and an internal support structure. The external clamping structure includes a locking cover (1), a support stud (5), a flange (6), and a nut (7). The support stud (5) has a screwing rod (55) in the middle. The lower threaded rod (57) at the lower end of the screwing rod (55) passes through the flange (6) and is locked by the nut (7). The upper threaded rod (54) at the upper end of the screwing rod (55) engages with the locking cover (1) to lock the large-diameter disc. The small-diameter disc extends upwards from the bottom surface (121) of the cover of the locking cover (1). The internal support structure includes an upper support. The upper support block (2) and the lower support block (3) include an upper support head (23) and a hollow threaded rod (25), and the whole has a shaft positioning hole (22) and an upper opening groove (21); the lower support block (3) has a second threaded hole (32) and a lower opening groove (31); the hollow threaded rod (25) cooperates with the second threaded hole (32), and when the upper opening groove (21) and the lower opening groove (31) are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk, and the large diameter disk and the small diameter disk are supported by adjusting the distance between the upper support block (2) and the lower support block (3).

2. The tooling for machining the differential diameter double gear shaft according to claim 1, characterized in that: The outer circle of the locking cover (1) has knurling (11), the inside has a first threaded hole (13), and there is a through hole (12) at the bottom of the cover body. The hole diameter can pass through the small diameter disc, but cannot pass through the large diameter disc.

3. The tooling for machining the differential diameter double gear shaft according to claim 1, characterized in that: The upper support head (23) supports the inner end face of the small-diameter disk through the outer end face of the upper support head (23), and the annular surface of the upper support head (23) has an upper parallel surface (24) for operation.

4. The tooling for machining the differential diameter double gear shaft according to claim 1, characterized in that: The lower support block (3) has a lower parallel surface (33) for operation on its annular surface, and the outer end surface (34) of the lower support block (3) supports the inner end surface of the large-diameter disk.

5. The tooling for machining the differential diameter double gear shaft according to claim 1, characterized in that: The end face of the upper thread rod (54) of the support stud (5) is the positioning surface (52), and there is a shaft end positioning hole (51) at the center of the positioning surface (52) to position the outer end shaft of the large diameter disk.

6. The tooling for machining the differential diameter double gear shaft according to claim 5, characterized in that: A pin hole (53) is provided at the eccentric position of the positioning surface (52). One end of the positioning pin (4) is inserted into the pin hole (53), and the other end is locked in the large-diameter disk to be limited by the machined teeth.

7. The tooling for machining a double gear shaft with different diameters according to claim 6, characterized in that: The cranking rod (55) has a parallel surface for operation.

8. The tooling for machining the differential diameter double gear shaft according to claim 1, characterized in that: The upper end face (61) of the flange (6) is in contact with the lower end face (56) of the screwing rod (55). The flange (6) has evenly distributed radial long grooves (63). The screw passes through the long grooves (63) and is tightened on the gear hobbing machine.

9. A method for machining a double gear shaft with different diameters, using the tooling as described in any one of claims 1-8, characterized in that, The machining of teeth on a large-diameter disk includes the following steps: S1. Using the internal support structure, the hollow threaded rod (25) is screwed into the second threaded hole (32), and after the upper opening groove (21) and the opening groove (31) are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk. S2. Adjust the spacing between the upper support block (2) and the lower support block (3) to fit closely and support the large-diameter disk and the small-diameter disk; S3. During gear shaping, the outer end shaft of the small diameter disc is clamped on the three-jaw chuck fixture of the gear shaping machine, and the gear shaping machine is started to perform gear shaping on the large diameter disc; during gear hobbing, the outer end shaft of the small diameter disc is clamped on one end of the gear hobbing machine, and the outer end shaft of the large diameter disc is clamped on the other end of the gear hobbing machine to perform gear hobbing.

10. A method for machining a double gear shaft with different diameters, using the tooling as described in any one of claims 1-8, characterized in that: When machining the teeth of a small-diameter disk using gear hobbing, the following steps are included: S1. Insert the threaded rod (57) into the flange (6) and tighten it with the nut (7); install the flange (6) on the gear hobbing machine and tighten it. S2. Using the internal support structure, the hollow threaded rod (25) is screwed into the second threaded hole (32), and after the upper opening groove (21) and the opening groove (31) are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk. S3. Adjust the spacing between the upper support block (2) and the lower support block (3) to make them fit together and support the large-diameter disk and the small-diameter disk; S4. Press the locking cover (1) onto the end face of the large diameter disc and tighten it; S5. Start the gear shaping machine to perform gear shaping on the small-diameter disc; The following steps are included when hobbing the teeth of a pinion: S1. Using the internal support structure, the hollow threaded rod (25) is screwed into the second threaded hole (32), and after the upper opening groove (21) and the opening groove (31) are aligned, it is inserted into the shaft between the large diameter disk and the small diameter disk. S2. Adjust the spacing between the upper support block (2) and the lower support block (3) to fit closely and support the large-diameter disk and the small-diameter disk; S3. Clamp the outer end shaft of the large diameter disc at one end of the gear hobbing machine, and clamp the outer end shaft of the small diameter disc at the other end of the gear hobbing machine. S4: Start the gear hobbing machine to perform gear hobbing on the small gear of the part.

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