Spline shifting device

Abstract

The utility model discloses a spline gear shifting device, include: spline shaft, assemble on the spline shaft with the spline shaft forms the spline pair's first spline cover and second spline cover and be used for locking the locking structure of first spline cover and second spline cover, first spline cover includes with first internal tooth of spline shaft cooperation, and be used for the first external tooth of gear shifting, second spline cover includes with second internal tooth of spline shaft cooperation, and be used for the second external tooth of gear shifting, first external tooth with second external tooth are all drum shape tooth. The utility model discloses a spline gear shifting device will be used for the single spline of traditional cooperation with the yoke transmission with the double drum shape spline assembly combination structure of tooth profile modification, namely the combination of first spline cover and second spline cover, has improved the spline pair tooth surface stress distribution for gear shifting, reduces the eccentric wear and tear, has improved the reliability and wear resistance degree of gear shifting device.

Description

Technical Field

[0001] This utility model relates to the field of gear shifting, and more specifically, to a spline shifting device. Background Technology

[0002] Modern gear transmission devices are generally highly integrated, with the shift spline pair serving as a core transmission component, and its design and application are very widespread. By shifting between different shaft systems, different speeds and torques can be transmitted to adapt to complex product process requirements. For example, metallurgical wire rod mills need to be compatible with dozens of wire diameters, and petrochemical mixing equipment needs to switch between high and low speeds to match the mixing requirements of different materials.

[0003] However, under actual working loads, the shifting device is prone to torsional deformation, which not only leads to uneven load distribution (i.e., off-center loading) but also generates axial force. Especially when long-term wear increases, the axial force will be further aggravated, and in severe cases, it may cause the shifting device to disengage, posing a major threat to production efficiency and personnel safety. Utility Model Content

[0004] This utility model aims to overcome at least one of the defects of the prior art and provides a spline shifting device to solve the problem that the shifting device in the prior art is prone to torsional deformation, which not only leads to uneven load distribution (i.e., off-center loading) but also generates axial force; especially when long-term wear increases the wear, the axial force will be further aggravated, and in severe cases, it may cause the shifting device to disengage, posing a major hidden danger to production efficiency and personnel safety.

[0005] The technical solution adopted by this utility model is as follows: A spline shifting device includes: a spline shaft, a first spline sleeve and a second spline sleeve mounted on the spline shaft and forming a spline pair with the spline shaft, and a locking structure for locking the first spline sleeve and the second spline sleeve; the first spline sleeve includes a first internal tooth that mates with the spline shaft and a first external tooth for shifting, the second spline sleeve includes a second internal tooth that mates with the spline shaft and a second external tooth for shifting, wherein both the first external tooth and the second external tooth are drum-shaped teeth.

[0006] In one embodiment, the common normals of the first internal tooth and the second internal tooth are the same; the common normals of the first external tooth and the second external tooth are the same.

[0007] In one embodiment, the first inner tooth and the second inner tooth are aligned and have the same phase, and the first outer tooth and the second outer tooth are aligned and have the same phase.

[0008] In one embodiment, the assembly accuracy of the first external tooth and the second external tooth is within level 6.

[0009] In one embodiment, the first spline sleeve and the second spline sleeve are further provided with mutually cooperating positioning steps.

[0010] In one embodiment, the locking structure includes bolts passing through the first spline sleeve and the second spline sleeve.

[0011] In one embodiment, the locking structure further includes a pin that passes through the first spline sleeve and the second spline sleeve and is interference-fitted with the first spline sleeve and the second spline sleeve.

[0012] In one embodiment, the number of bolts is multiple, and the multiple bolts are spaced apart along the circumferential direction of the first spline sleeve and the second spline sleeve.

[0013] In one embodiment, the number of pins is multiple, and the pins are staggered with the bolts.

[0014] In one embodiment, the spline shaft is provided with a first shoulder and a second shoulder for radially positioning the first spline sleeve and the second spline sleeve.

[0015] Compared with the prior art, the beneficial effects of this utility model include at least the following: Gear shifting devices typically include a shift fork, with the internal spline centered in the neutral position. When the left gear engages, the internal spline is shifted to the left working position A. In traditional gear shifting devices, both the internal and external splines used for shifting employ a spur involute structure. Under load, the splines undergo torsional deformation, generating axial force. During the initial use of new equipment, spline wear is minimal, and friction effectively constrains the spline position, thus preventing gear slippage. However, as the equipment operates, spline wear accumulates, especially at the ends, widening the clearance and creating a ramp that further increases axial force, eventually leading to gear slippage.

[0016] This technical solution's spline shifting device decomposes the traditional single spline used for engagement with the shift fork into a double-drum spline assembly structure with toothed profile modification, namely, the combination of the first spline sleeve and the second spline sleeve. This improves the stress distribution on the spline tooth surface used for shifting, reduces off-center wear, and enhances the reliability and wear resistance of the shifting device. Specifically, when the left gear enters the transmission mode, the inner spline of the shift fork is shifted to the left working position A. The left part of the inner spline engages with the left gear, and the right part engages with the first spline sleeve. The rotation of the first external tooth drives the rotation of the inner tooth of the shift fork, which in turn drives the rotation of the outer tooth of the left gear. Since the first external tooth of the first spline sleeve is a drum-shaped tooth, the maximum stress point of the first external tooth is concentrated in the middle position, and the wear area also shifts towards the middle. This design effectively avoids the formation of sloping wear on the tooth surface, thereby reducing the generation of axial force and lowering the possibility of gear disengagement. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the spline shifting device according to an embodiment of the present invention.

[0018] Figure 2 for Figure 1 A magnified view of part B in the diagram.

[0019] Figure 3 This is a schematic diagram showing the distribution of the locking structure according to an embodiment of the present invention.

[0020] Reference numerals: 10, splined shaft; 11, first shoulder; 12, second shoulder; 20, first splined sleeve; 21, first external gear; 30, second splined sleeve; 31, second external gear; 41, bolt; 42, pin; 50, shift fork; 60, left gear; 70, right gear; 80, positioning step. Detailed Implementation

[0021] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this invention. To better illustrate the following embodiments, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0022] like Figures 1-3The spline shifting device shown includes: a spline shaft 10, a first spline sleeve 20 and a second spline sleeve 30 mounted on the spline shaft 10 and forming a spline pair with the spline shaft 10, and a locking structure for locking the first spline sleeve 20 and the second spline sleeve 30; the first spline sleeve 20 includes a first internal tooth that mates with the spline shaft 10 and a first external tooth 21 for shifting, the second spline sleeve 30 includes a second internal tooth that mates with the spline shaft 10 and a second external tooth 31 for shifting, and both the first external tooth 21 and the second external tooth 31 are drum-shaped teeth.

[0023] The shifting device typically includes a shift fork 50, with its neutral position corresponding to the centered internal spline. When the left gear 60 enters the transmission mode, the internal spline is shifted to the left working position A. In traditional shifting devices, both the internal and external splines used for shifting employ a spur involute structure. Under load, the splines undergo torsional deformation, generating axial force. During the initial use of newly commissioned equipment, spline wear is low, and friction effectively constrains the spline position, thus preventing gear slippage. However, as the equipment operates, spline wear accumulates, especially at the ends, widening the clearance and creating a slope that further increases axial force, eventually leading to gear slippage.

[0024] The spline shifting device of this embodiment decomposes the traditional single spline used for transmission with the shift fork 50 into a double-drum spline assembly structure with toothed modification, namely the combination of the first spline sleeve 20 and the second spline sleeve 30. This improves the stress distribution on the spline tooth surface used for shifting, reduces off-center wear, and improves the reliability and wear resistance of the shifting device. Specifically, in the initial position, the inner spline of the shift fork 50 is centered in the neutral position C. When the left gear 60 enters the transmission condition, the inner spline of the shift fork 50 is shifted to the left working position A. The left part of the inner spline is in transmission engagement with the left gear 60, and the right part of the inner spline is in transmission engagement with the first spline sleeve 20. The rotation of the first external tooth 21 drives the rotation of the inner tooth of the shift fork 50, which in turn drives the rotation of the outer tooth of the left gear 60. Since the first external tooth 21 of the first spline sleeve 20 is a drum-shaped tooth, the maximum stress point of the first external tooth 21 is concentrated in the middle position, and the wear area also shifts to the middle. Conversely, when the internal spline of the shift fork 50 is shifted to the right working position, the right side of the internal spline engages with the right gear 70, and the left side of the internal spline engages with the second spline sleeve 30. This design effectively prevents the formation of a sloping wear on the tooth surface, thereby reducing the generation of axial force and lowering the possibility of gear disengagement.

[0025] In this embodiment, the common normals of the first internal teeth and the second internal teeth are consistent; the common normals of the first external teeth 21 and the second external teeth 31 are consistent. This unifies the meshing reference of the first spline sleeve 20 and the second spline sleeve 30, ensuring transmission accuracy while reducing assembly difficulty and improving product compatibility.

[0026] In this embodiment, the first inner tooth and the second inner tooth are aligned and have the same phase, and the first outer tooth 21 and the second outer tooth 31 are aligned and have the same phase. Through the above design, this embodiment ensures that the first outer tooth 21 and the second outer tooth 31 have the same drum shape, the same tooth thickness, and the same tooth distribution after assembly. The first outer tooth 21 and the second outer tooth 31 do not intersect, thereby improving the transmission accuracy.

[0027] Specifically, in this embodiment, after the first spline sleeve 20 and the second spline sleeve 30 are assembled, the assembly accuracy of the first external tooth 21 and the second external tooth 31 is within level 6, and level 5 accuracy can be selected to make the assembly error within 2 microns.

[0028] In this embodiment, the first spline sleeve 20 and the second spline sleeve 30 are also provided with mutually cooperating positioning steps 80. That is, the first spline sleeve 20 and the second spline sleeve 30 are initially radially positioned by setting the journal φD2. After ensuring that the first external tooth 21 and the second external tooth 31 are in phase, the first spline sleeve 20 and the second spline sleeve 30 are locked by a locking structure.

[0029] The locking structure described in this embodiment includes a bolt 41 that passes through the first spline sleeve 20 and the second spline sleeve 30. When the first spline sleeve 20 and the second spline sleeve 30 are radially positioned by the journal φD2 to ensure that the first external tooth 21 and the second external tooth 31 are in phase, the first spline sleeve 20 and the second spline sleeve 30 are locked by the bolt 41.

[0030] When the load is large, pin holes can be added to the first spline sleeve 20 and the second spline sleeve 30. The locking structure also includes a pin 42 that passes through the first spline sleeve 20 and the second spline sleeve 30 and is interference-fitted with the pin holes on the first spline sleeve 20 and the second spline sleeve 30 to accurately transmit torque.

[0031] To ensure locking strength, the number of bolts 41 in this embodiment is multiple, and the multiple bolts 41 are spaced apart along the circumferential direction of the first spline sleeve 20 and the second spline sleeve 30.

[0032] Similarly, the number of pins 42 can also be set to multiple, and the pins 42 and the bolts 41 are arranged alternately.

[0033] The spline shaft 10 described in this embodiment is provided with a first shoulder 11 and a second shoulder 12 for radial positioning of the first spline sleeve 20 and the second spline sleeve 30, that is, at the positions of φD1 and φD3 in the figure. The first shoulder 11 and the second shoulder 12 are used to perform static radial precise positioning of the first spline sleeve 20 and the second spline sleeve 30. After being subjected to load, the involute spline pair is used for automatic centering and positioning.

[0034] When the assembly consisting of the first spline sleeve 20, the second spline sleeve 30 and the locking structure is assembled with the spline shaft 10, a large interference fit can be selected and the interference amount can be checked; a trapezoidal spline can also be used, a rectangular spline can be used if the load is light, and a flat key or double flat key can be used if the size is sufficient.

[0035] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the technical solution of this utility model, and are not intended to limit the specific implementation of this utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the claims of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A spline shifting device, characterized in that, include: A spline shaft, a first spline sleeve and a second spline sleeve assembled on the spline shaft and forming a spline pair with the spline shaft, and a locking structure for locking the first spline sleeve and the second spline sleeve; the first spline sleeve includes a first internal tooth that mates with the spline shaft and a first external tooth for shifting gears, the second spline sleeve includes a second internal tooth that mates with the spline shaft and a second external tooth for shifting gears, both the first external tooth and the second external tooth being drum-shaped teeth.

2. The spline shifting device according to claim 1, characterized in that, The common normals of the first internal tooth and the second internal tooth are the same; the common normals of the first external tooth and the second external tooth are the same.

3. The spline shifting device according to claim 1, characterized in that, The first inner tooth and the second inner tooth are aligned and have the same phase, and the first outer tooth and the second outer tooth are aligned and have the same phase.

4. The spline shifting device according to claim 3, characterized in that, The assembly accuracy of the first external tooth and the second external tooth is within level 6.

5. The spline shifting device according to claim 1, characterized in that, The first spline sleeve and the second spline sleeve are also provided with positioning steps that cooperate with each other.

6. The spline shifting device according to claim 1, characterized in that, The locking structure includes bolts that pass through the first spline sleeve and the second spline sleeve.

7. The spline shifting device according to claim 6, characterized in that, The locking structure also includes a pin that passes through the first spline sleeve and the second spline sleeve and is interference-fitted with the first spline sleeve and the second spline sleeve.

8. The spline shifting device according to claim 6, characterized in that, The number of bolts is multiple, and the multiple bolts are spaced apart along the circumferential direction of the first spline sleeve and the second spline sleeve.

9. The spline shifting device according to claim 7, characterized in that, The number of pins is multiple, and the pins and bolts are arranged alternately.

10. The spline shifting device according to any one of claims 1-9, characterized in that, The splined shaft is provided with a first shoulder and a second shoulder for radial positioning of the first spline sleeve and the second spline sleeve.

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