Heavy load equipped sinusoidal modified profile - multi-step sinusoidal transmission ratio hypoid gear differential

Abstract

The present application relates to a kind of heavy load equipment sinusoidal modification profile multi-stage sinusoidal transmission ratio non-circular gear differential device, including shell, arc tooth big wheel, planet carrier, planet gear, adjusting washer, right half axle, half axle gear, left half axle, input shaft and cross shaft, the shell is installed on the bridge of vehicle, the transmission shaft of vehicle is connected with input shaft by spline or shaft coupling, input shaft is installed on the box by bearing, planet carrier is installed on the box by bearing, half axle gear is installed inside the shell by bearing, arc tooth big wheel is installed on planet carrier by center positioning and is engaged with the tooth surface of input shaft inner end, cross shaft is installed on planet carrier, planet gear is installed on cross shaft by center inner hole.The present application realizes the change of differential transmission ratio by the uniform change of planet wheel and half axle wheel speed ratio of high-order non-circular gear, and then the torque ratio of left and right half axle of car changes, so that certain antiskid function is realized.

Description

Technical Field

[0001] This invention relates to the field of automotive transmission, and more specifically, to a non-circular gear differential device with sinusoidal modified tooth profile and multi-stage sinusoidal transmission ratio for heavy-duty equipment. Background Technology

[0002] Chinese patent CN1487222A proposes a variable-ratio anti-slip differential, which achieves a varying transmission ratio through a high-low gear design. However, the gears designed using this method have discontinuous transmission ratios, poor smoothness, and high noise. Chinese patent CN101839307A proposes a variable transmission ratio anti-slip differential, which still uses a high-low gear design, but achieves tooth surface design by solving for the instantaneous meshing point of the gears. The designed tooth profile has theoretical meshing performance, but the transmission ratio is uncontrollable. Chinese patent CN101900193A discloses a non-circular planetary gear limited-slip differential, but it uses a low-order non-circular gear design and only has two half-shaft gears, limiting its application in heavy-duty vehicles. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a heavy-duty equipment sine modified tooth profile-multi-stage sine transmission ratio non-circular gear differential device, which realizes the uniform change of the speed ratio of planetary gears and half-shaft gears through high-stage non-circular gears to achieve the change of transmission ratio during differential speed, thereby changing the torque ratio of the left and right half-shafts of the vehicle, thus achieving a certain anti-skid function.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows: A non-circular gear differential device with sinusoidal modified tooth profile and multi-stage sinusoidal transmission ratio for heavy-duty equipment is constructed, comprising a housing, a large arc-tooth gear, a planetary carrier, planetary gears, adjusting shims, a right half-shaft, a half-shaft gear, a left half-shaft, an input shaft, and a cross shaft. The housing is mounted on the vehicle's axle. The vehicle's drive shaft and input shaft are connected by a spline or coupling. The input shaft is mounted on the housing via bearings. The planetary carrier is mounted on the housing via bearings. The half-shaft gears are mounted inside the housing via bearings. The large arc-tooth gear is centrally positioned and mounted on the planetary carrier, meshing with the tooth surface at the inner end of the input shaft. The cross shaft is mounted on the planetary carrier. The planetary gears are mounted on the cross shaft through a central inner hole. There are four planetary gears and two half-shaft gears. Each planetary gear meshes with the half-shaft gears on the left and right sides. The half-shaft gears have spline grooves in the middle that connect to the left and right half-shafts respectively. Adjusting shims are installed between the back conical surface of the planetary gear and the inner surface of the mounting hole of the planetary carrier to adjust the clearance between the planetary gears and the half-shaft gears.

[0005] According to the above scheme, both the planetary gears and the half-shaft gears are multi-stage non-circular gears, and their transmission ratio is expressed as follows:

[0006] In the formula, This refers to the rotation angle of the planetary gear; A coefficient related to differential characteristics; The transmission cycle of the driving wheel; The phase angle of the transmission; The transmission ratio is an undetermined coefficient, which is obtained by adjusting parameters. For the driving and driven wheels to complete a full revolution, the following relationship must be satisfied:

[0007] In the formula, The transmission cycle of the driven wheel.

[0008] According to the above scheme, the modification of the multi-stage non-circular gear is achieved through the meshing principle, which includes the following steps: S1. Solve for the pitch surface of a non-circular gear using the following formula:

[0009] In the formula and These are the pitch curve equations for the planetary gear and the half-shaft gear, respectively. These are the pitch cone angles of the pitch surfaces of the planetary gear and the half-shaft gear, respectively. The rotation angle of the non-circular gear on the half-shaft. and Both are functions of the planetary gear rotation angle, calculated using the following formula: ; S2. A sinusoidal bevel gear is used as the generating gear. The tooth profile of the generating gear is obtained by projecting a sinusoidal rack onto a spherical surface. The equation of the sinusoidal rack tooth profile is:

[0010] In the formula, Let be the parameter of the equation of the rack along the curve. This is the tooth surface coefficient; the larger the value, the steeper the tooth surface. Let be the radius of the sphere of the gear. ,in The radius of the sphere at the smaller end is 3. The radius of the large end sphere; The module of the gear on different spherical surfaces is calculated by dividing the arc length of the planetary gear pitch surface by the number of teeth. To obtain, that is:

[0011] After being projected onto the sphere, the tooth profile equation of the generating gear is:

[0012] In the formula, , The cone angle and polar angle of the feed wheel are calculated using the following formula:

[0013] S3. Use a quadratic polynomial function to modify the tooth tip and tooth root of the forming wheel. The modification function is as follows:

[0014] In the formula, This is the profile modification function along the tooth length direction. These are the corresponding polynomial shaping parameters. This is the profile modification function in the direction of the gear tooth profile. These are the corresponding polynomial shaping parameters; The equation of the modified tooth surface is:

[0015] In the formula , The cone angle and polar angle of the formed wheel after shaping; S4. Based on the tangency between the generating wheel and the pitch surface of the non-circular gear, the motion envelope relationship between the generating wheel and the non-circular bevel gear is obtained as follows:

[0016] In the formula, These represent the unit normal vector, circumferential pitch vector, and radial pitch vector of the non-circular gear pitch curve, respectively. The rotation angle of the feed wheel is calculated using the following formula:

[0017] In the formula, For non-circular gears, the rotation angle and pitch cone angle are used when generating planetary non-circular gears. When generating a non-circular gear half-shaft, ; S5. Based on the kinematic relationship of the generating gear and the tooth profile equation of the generating gear, the tooth profile of the non-circular gear can be obtained, and calculated using the following formula.

[0018] In the formula, and The tooth profile envelope equations for the unmodified and modified non-circular gears are given respectively. Combined with the gear meshing equation, the tooth profile equation is obtained. S6. Based on the above tooth profile equation, establish the three-dimensional models of the planetary gear and the half-shaft gear.

[0019] According to the above scheme, for planetary gears and half-shaft gears formed by die forging, the tooth height modification and tooth tip modification are relatively large, while the tooth root modification is small, to ensure correct meshing after the tooth surface is deformed.

[0020] For the tooth length direction, the large end is modified to be larger, and the contact area is controlled at approximately 1 / 3 of the way towards the small end of the gear, that is: .

[0021] The heavy-duty equipment sinusoidal modified tooth profile-multi-stage sinusoidal transmission ratio non-circular gear differential device of the present invention has the following beneficial effects: 1. This invention proposes the concept of non-circular gear transmission, which generates a pair of conjugate high-order non-circular gears by using a given high-order transmission ratio and achieves dynamic adjustment of the contact area by modifying the shape of the generating wheel; 2. This invention proposes a multi-stage modified non-circular gear differential device. By using high-order non-circular gears to achieve a uniform change in the speed ratio between the planetary gears and the half-shaft gears, the transmission ratio changes during differential operation, thereby altering the torque ratio between the left and right half-shafts of the vehicle and achieving a certain anti-slip function. A high-order sinusoidal transmission ratio is used to distribute torque. A forming wheel is used to generate the tooth surfaces of a pair of conjugate non-circular gears, and the tooth surfaces of the conjugate non-circular gears are modified by modifying the forming wheel.

[0022] 3. This invention employs a high-order sinusoidal transmission ratio to achieve torque distribution. It generates the tooth surfaces of a pair of conjugate non-circular gears through a forming wheel, and modifies the tooth surfaces of the conjugate non-circular gears by modifying the forming wheel. Its design method achieves complete conjugation in principle, fully considers manufacturing and assembly errors, and results in smooth transmission, low noise, and high load-bearing capacity. The tooth surfaces can be formed by die forging, resulting in low cost and suitability for mass production. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 A schematic diagram of the structure of the heavy-duty equipment sinusoidal modified tooth profile-multi-stage sinusoidal transmission ratio non-circular gear differential device of the present invention. Figure 2 The transmission ratio function shape used for 3rd and 4th order non-circular gears; Figure 3 A schematic diagram of the tooth profile of the half-shaft gear in a 3rd or 4th order non-circular gear; Figure 4 A schematic diagram of the tooth surface of a planetary gear in a non-circular gear of order 3-4; Figure 5 This is a schematic diagram of the overall meshing situation in non-circular gears of order 3-4; Figure 6 The transmission ratio function shape used for 2nd to 4th order non-circular gears; Figure 7 This is a schematic diagram of the tooth profile of the half-shaft gear in non-circular gears of orders 2-4; Figure 8 Schematic diagram of the tooth surface of planetary gears in non-circular gears of orders 2-4; Figure 9 This is a schematic diagram of the overall meshing situation in non-circular gears of orders 2-4; Detailed Implementation To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] like Figure 1-9 As shown, the heavy-duty equipment sine modified tooth profile-multi-stage sine transmission ratio non-circular gear differential device of the present invention includes a housing 1, an arc toothed large wheel 2, a planetary carrier 3, a cross shaft 4, a planetary gear 5, an adjusting shim 6, a right half shaft 7, a half shaft gear 8, a left half shaft 9, and an input shaft 10.

[0025] The differential device of the present invention is installed as follows: the housing 1 is installed on the axle of the vehicle, the drive shaft of the vehicle is connected to the input shaft 10 by a spline or a coupling, the input shaft 10 is installed on the housing by a bearing, the planetary carrier 3 is installed on the housing by a bearing, the half-shaft gear 8 is installed inside the housing 1 by a bearing, the large arc gear 2 is installed on the planetary carrier 3 by a center positioning and meshes with the tooth surface of the inner end of the input shaft 10, the cross shaft 4 is installed on the planetary carrier 3, the planetary gear 5 is installed on the cross shaft 4 through the central inner hole, there are four planetary gears 5 and two half-shaft gears 8, each planetary gear 5 meshes with the half-shaft gears 8 on the left and right sides, the half-shaft gear 8 has a spline groove in the middle that is connected to the left half-shaft 9 and the right half-shaft 7 respectively, and the adjusting shim 6 is installed between the back cone surface of the planetary gear and the inner surface of the mounting hole of the planetary carrier 3 to adjust the clearance between the planetary gear 5 and the half-shaft gear 8.

[0026] When the vehicle is traveling in a straight line, the drive shaft drives the input shaft 10 of the differential equipment to rotate. The input shaft 10 drives the large arc gear 2 that meshes with it to rotate, thereby driving the planetary carrier 3 to rotate. Since the torque of the left half-shaft 9 and the right half-shaft 7 is equal at this time, it forces the left and right half-shaft 7 gears to rotate synchronously with the planetary carrier 3, thereby driving the left half-shaft 9 and the right half-shaft 7 to rotate at the same speed and in the same direction. When the vehicle turns, due to the action of ground friction, the torque of the left half-shaft 9 and the right half-shaft 7 will change, resulting in a torque difference between the left half-shaft 9 and the right half-shaft 7, which forces the planetary gear 5 to rotate. Since the planetary gear 5 is a non-conical gear, the radius of its meshing point will continuously change during its rotation, thereby generating a certain resistance and preventing the planetary gear 5 from continuously accelerating, which plays a role in limiting vehicle slippage.

[0027] Both planetary gears and axle gears are multi-stage non-circular gears, and their transmission ratio is expressed as follows:

[0028] In the formula, This refers to the rotation angle of the planetary gear; A coefficient related to differential characteristics. The larger the diameter, the better the anti-slip performance of the entire device, but the worse its differential performance. The smaller the size, the worse the anti-slip performance of the device, but the better the differential performance. It needs to be selected comprehensively based on road conditions. The transmission cycle of the drive wheel is the largest possible transmission cycle. The larger the transmission cycle, the better the dynamic differential performance of the differential and the smaller the maximum differential ratio. The phase angle of the transmission is used to adjust the positional relationship between the tooth profile and the pitch curve. Through reasonable design, the root height of the tooth surface can be eliminated to the greatest extent and the differential ratio can be improved. The transmission ratio is an undetermined coefficient, which is obtained by adjusting parameters. This allows the driving and driven wheels to rotate a full revolution, satisfying the following relationship:

[0029] In the formula, The transmission cycle of the driven wheel.

[0030] The modification of multi-stage non-circular gears is achieved through the meshing principle, which includes the following steps: S1. Solve for the pitch surface of a non-circular gear using the following formula:

[0031] In the formula and These are the pitch curve equations for the planetary gear and the half-shaft gear, respectively. These are the pitch cone angles of the pitch surfaces of the planetary gear and the half-shaft gear, respectively. The rotation angle of the non-circular gear on the half-shaft. and Both are functions of the planetary gear rotation angle, calculated using the following formula: ; S2. A sinusoidal bevel gear is used as the generating gear. The tooth profile of the generating gear is obtained by projecting a sinusoidal rack onto a spherical surface. The equation of the sinusoidal rack tooth profile is:

[0032] In the formula, Let be the parameter of the equation of the rack along the curve. This is the tooth surface coefficient; the larger the value, the steeper the tooth surface. It is generally selected based on actual needs. ,in The radius of the sphere at the smaller end is 3. Let be the radius of the larger end of the sphere. The module of a gear on different spherical surfaces can be calculated by dividing the arc length of the planetary gear pitch surface by the number of teeth. To obtain, that is:

[0033] After being projected onto the sphere, the tooth profile equation of the generating gear is:

[0034] In the formula, , The cone angle and polar angle of the feed wheel are calculated using the following formula:

[0035] S3. Use a quadratic polynomial function to modify the tooth tip and tooth root of the forming wheel. The modification function is as follows:

[0036] In the formula, This is the profile modification function along the tooth length direction. These are the corresponding polynomial shaping parameters. This is the profile modification function in the direction of the gear tooth profile. These are the corresponding polynomial shaping parameters; The equation of the modified tooth surface is:

[0037] In the formula , The cone angle and polar angle of the formed wheel after shaping; S4. Based on the tangency between the generating wheel and the pitch surface of the non-circular gear, the motion envelope relationship between the generating wheel and the non-circular bevel gear is obtained as follows:

[0038] In the formula, These represent the unit normal vector, circumferential pitch vector, and radial pitch vector of the non-circular gear pitch curve, respectively. The rotation angle of the feed wheel is calculated using the following formula:

[0039] In the formula, For non-circular gears, the rotation angle and pitch cone angle are used when generating planetary non-circular gears. When generating a non-circular gear half-shaft, ; S5. Based on the kinematic relationship of the generating gear and the tooth profile equation of the generating gear, the tooth profile of the non-circular gear can be obtained, and calculated using the following formula.

[0040] In the formula, and The tooth profile envelope equations for the unmodified and modified non-circular gears are given respectively. Combined with the gear meshing equation, the tooth profile equation is obtained. S6. Based on the above tooth profile equation, establish the three-dimensional models of the planetary gear and the half-shaft gear.

[0041] Furthermore, for planetary gears and half-shaft gears formed by die forging, the tooth height and tooth tip modification are relatively large, while the tooth root modification is small, to ensure correct meshing after the tooth surface is deformed.

[0042] For the tooth length direction, the large end is modified to be larger, and the contact area is controlled at approximately 1 / 3 of the way towards the small end of the gear, that is: .

[0043] The specific gear parameters of the embodiment of the heavy-duty equipment sinusoidal modified tooth profile-multi-stage sinusoidal transmission ratio non-circular gear differential device of the present invention are shown in Table 1: Table 1 Parameters of Non-Bevel Gears

[0044] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A non-circular gear differential device with sinusoidal modified tooth profile and multi-stage sinusoidal transmission ratio for heavy-duty equipment, characterized in that, The system includes a housing, a large spiral gear, a planetary carrier, planetary gears, adjusting shims, a right half-shaft, a half-shaft gear, a left half-shaft, an input shaft, and a cross shaft. The housing is mounted on the vehicle's axle. The vehicle's drive shaft and input shaft are connected via splines or couplings. The input shaft is mounted on the housing via bearings. The planetary carrier is mounted on the housing via bearings. The half-shaft gears are mounted inside the housing via bearings. The large spiral gear is centrally positioned and mounted on the planetary carrier, meshing with the tooth surface at the inner end of the input shaft. The cross shaft is mounted on the planetary carrier. The planetary gears are mounted on the cross shaft through a central inner hole. There are four planetary gears and two half-shaft gears. Each planetary gear meshes with the half-shaft gears on the left and right sides. The half-shaft gears have spline grooves in the middle that connect to the left and right half-shafts respectively. Adjusting shims are installed between the back conical surface of the planetary gear and the inner surface of the mounting hole of the planetary carrier to adjust the clearance between the planetary gears and the half-shaft gears. Both the planetary gears and the half-shaft gears are multi-stage non-circular gears, and their transmission ratio is expressed as follows: In the formula, This refers to the rotation angle of the planetary gear; A coefficient related to differential characteristics; The transmission cycle of the driving wheel; The phase angle of the transmission; The transmission ratio is an undetermined coefficient, which is obtained by adjusting parameters. For the driving and driven wheels to complete a full revolution, the following relationship must be satisfied: In the formula, The transmission cycle of the driven wheel; The modification of the multi-stage non-circular gear is achieved through the meshing principle, which includes the following steps: S1. Solve for the pitch surface of a non-circular gear using the following formula: In the formula and These are the pitch curve equations for the planetary gear and the half-shaft gear, respectively. These are the pitch cone angles of the pitch surfaces of the planetary gear and the half-shaft gear, respectively. The rotation angle of the non-circular gear on the half-shaft. and Both are functions of the planetary gear rotation angle, calculated using the following formula: ； S2. A sinusoidal bevel gear is used as the generating gear. The tooth profile of the generating gear is obtained by projecting a sinusoidal rack onto a spherical surface. The equation of the sinusoidal rack tooth profile is: In the formula, Let be the parameter of the equation of the rack along the curve. This is the tooth surface coefficient; the larger the value, the steeper the tooth surface. Let be the radius of the sphere of the gear. ,in The radius of the sphere at the smaller end is 3. The radius of the large-end sphere; The module of the gear on different spherical surfaces is calculated by dividing the arc length of the planetary gear pitch surface by the number of teeth. To obtain, that is: After being projected onto the sphere, the tooth profile equation of the generating gear is: In the formula, , The cone angle and polar angle of the feed wheel are calculated using the following formula: S3. Use a quadratic polynomial function to modify the tooth tip and tooth root of the forming wheel. The modification function is as follows: In the formula, This is the profile modification function along the tooth length direction. For the corresponding polynomial shaping parameters, This is the profile modification function in the direction of the gear tooth profile. These are the corresponding polynomial shaping parameters; The equation for the modified tooth surface is: In the formula , The cone angle and polar angle of the formed wheel after shaping; S4. Based on the tangency between the generating wheel and the pitch surface of the non-circular gear, the motion envelope relationship between the generating wheel and the non-circular bevel gear is obtained as follows: In the formula, These represent the unit normal vector, circumferential pitch vector, and radial pitch vector of the non-circular gear pitch curve, respectively. The rotation angle of the feed wheel is calculated using the following formula: In the formula, For non-circular gears, the rotation angle and pitch cone angle are used when generating planetary non-circular gears. When generating a non-circular gear half-shaft, ; S5. Based on the kinematic relationship of the generating gear and the tooth profile equation of the generating gear, the tooth profile of the non-circular gear can be obtained, and calculated using the following formula. In the formula, and The tooth profile envelope equations for the unmodified and modified non-circular gears are given respectively. Combined with the gear meshing equation, the tooth profile equation is obtained. S6. Based on the above tooth profile equation, establish the three-dimensional models of the planetary gear and the half-shaft gear.

2. The heavy-duty equipment sinusoidal modified tooth profile-multi-stage sinusoidal transmission ratio non-circular gear differential device according to claim 1, characterized in that, For planetary gears and half-shaft gears formed by die forging, the tooth height and tooth tip modification are relatively large, while the tooth root modification is small, to ensure proper meshing after the tooth surface is deformed. For the tooth length direction, the large end is modified to be larger, and the contact area is controlled at approximately 1 / 3 of the way towards the small end of the gear, that is: 。

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