CN109190214B - A planetary gear transmission mechanism and its design method - Google Patents

Abstract

The present invention relates to a design method of a planetary gear transmission mechanism, comprising the following steps: S1: constructing a model of a planetary gear mechanism, the planetary gear mechanism comprising: a casing with an internal gear formed on an inner peripheral wall, a planet carrier, a sun gear, at least one planetary gear set arranged on the planet carrier; the planetary gear set includes a coaxially arranged first planetary gear and a second planetary gear, the first planetary gear meshes with the sun gear, and the second planetary gear The wheel meshes with the internal gear; when the sun gear rotates, the planet carrier can be driven to rotate through the planetary gear set; S2: adjust the number of gears of the sun gear, the first planetary gear, the second planetary gear and the internal gear, so that the The angular velocity ratio of the sun gear and the planet carrier conforms to the preset target value, where the formula 1 is:

The planetary gear design method of this scheme can ensure that the designed transmission ratio of the planetary gear mechanism has high accuracy. The present application further provides a planetary gear transmission mechanism.

Description

A planetary gear transmission mechanism and its design method

technical field

The present invention relates to a planetary gear mechanism technology, in particular, to a planetary gear transmission mechanism and a design method thereof.

Background technique

At present, when calculating the transmission ratio of the hoist planetary gear transmission design, it is usually calculated according to the formula provided by the mechanical design theory. The logic of this method is poor, the scientific meaning expressed by the formula is difficult to understand and use, and the formula can only be hard-set when used. In view of this, this application is hereby made.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a design method of a planetary gear transmission mechanism to solve the problems of poor clarity and low design efficiency of the existing design method of the planetary gear mechanism.

根据齿轮分度圆处啮合点线速度相等的运动关系获得；其中，ω1为太阳轮1转动的角速度，ω7为行星架7转动的角速度，Z1、Z2、Z3和Z4分别为太阳轮1、第一行星轮2、第二行星轮3和内齿轮4的齿轮数。In order to solve the above-mentioned technical problems, the present invention provides a method for designing a planetary gear mechanism, which includes the following steps: S1: constructing a model of the planetary gear mechanism, the planetary gear mechanism includes: a casing 5 having an internal gear 4 formed on an inner peripheral wall , a planet carrier, a sun gear, and at least one planetary gear set arranged on the planet carrier; the planetary gear set includes a coaxially arranged first planetary gear and a second planetary gear, the first planetary gear and the sun gear Meshing, the second planetary gear meshes with the internal gear; when the sun gear rotates, the planet carrier can be driven to rotate through the planetary gear set; S2: Adjust the number of gears of the sun gear, the first planetary gear, the second planetary gear and the internal gear , so that the angular velocity ratio of the sun gear and the planet carrier calculated according to formula 1 meets the preset target value, where formula 1 is:

Obtained according to the kinematic relationship of equal linear velocity of meshing point at the gear index circle; wherein, ω1 is the angular velocity of the rotation of the sun gear 1, ω7 is the angular velocity of the rotation of the planet carrier 7, Z1, Z2, Z3 and Z4 are the angular velocity of the sun gear 1, the Number of gears of a planetary gear 2, a second planetary gear 3 and an internal gear 4.

By adopting the above technical scheme, the present invention can achieve the following technical effects: the planetary gear design method of this scheme can ensure that the number of gear teeth and the required transmission ratio of the planetary gear transmission system can be obtained by design, and the process is clear, the efficiency is high, and the quality is high.

其中，ω1为太阳轮(1)转动的角速度，ω7为行星架转动的角速度，Z1、Z2、Z3和Z4分别为太阳轮、第一行星轮、第二行星轮和内齿轮的齿轮数。The present application further provides a planetary gear transmission mechanism, comprising: a casing with an internal gear formed on an inner peripheral wall, a planet carrier, a sun gear, and at least one planetary gear set arranged on the planet carrier; the planetary gear set includes The first planetary gear and the second planetary gear are coaxially arranged, the first planetary gear is meshed with the sun gear, and the second planetary gear is meshed with the internal gear; when the sun gear rotates, it can drive the planet carrier through the planetary gear set Rotation; the angular velocity ratio of the sun gear and the planet carrier satisfies Formula 1; Formula 1 is:

Among them, ω1 is the angular velocity of the rotation of the sun gear (1), ω7 is the angular velocity of the rotation of the planet carrier, and Z1, Z2, Z3 and Z4 are the gear numbers of the sun gear, the first planetary gear, the second planetary gear and the internal gear, respectively.

Description of drawings

FIG. 1 shows a design idea of a planetary gear mechanism according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a planetary gear mechanism according to an embodiment of the present application;

FIG. 3 shows a view corresponding to the direction B-B of FIG. 2;

FIG. 4 shows a view corresponding to the direction A-A of FIG. 2;

FIG. 5 and FIG. 6 are schematic diagrams of the planetary gear mechanism based on the principle diagram of FIG. 2 under different viewing angles, respectively.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention.

1, in one embodiment, the design method of the planetary gear transmission mechanism of the present application roughly includes the following steps: 1. Building a planetary gear mechanism model; 2. Establishing a linear velocity relationship model; 3. Establishing a known condition model; 4. Solve; 5. End.

2 to 6 , the model of the planetary gear mechanism constructed in this embodiment includes: a casing 5 with an internal gear 4 formed on the inner peripheral wall, a planetary carrier 7 , a sun gear 1 , and two arranged on the planetary carrier 7 The planetary gear set 9; the planetary gear set 9 includes the first planetary gear 2 and the second planetary gear 3 arranged coaxially (that is, the axes of the two coincide and can rotate synchronously), the first planetary gear 2 meshes with the sun gear 1, and the first planetary gear The two planetary gears 3 mesh with the internal gear 4 ; when the sun gear 1 rotates, the planetary carrier 7 can be driven to rotate through the planetary gear set 9 . 2, in the actual product, the surface of the housing 5 can also be formed with a hook 6, the sun gear can be driven by the power input wheel 8, the hook 6 and the power input wheel 8 are not shown in Figures 5 and 6. O1 represents the rotation centerline of the sun gear 1 and the power input wheel 8, O2 represents the rotation centerline of the first planetary gear 2, O3 represents the rotation centerline of the second planetary gear 3, and O2O3 represents the first planetary gear 2 and the second planetary gear. The rotation axis line of the wheel 3, O7 is the rotation center line of the planet carrier 7. A-A and B-B are codes for drawing cross-sectional views. The power input by the power input wheel 8 transmits power to the first planetary gear 2 through the meshing of the sun gear 1 and the first planetary gear 2. The first planetary gear 2 transmits the power through the second planetary gear 3 and the internal gear 4, and at the same time passes through its inner hole. Drive the planetary carrier 7 to output power. It should be noted that, Fig. 5 and Fig. 6 do not show the teeth on each gear member.

FIG. 3 shows the transmission relationship of the sun gear 1 , the first planetary gear 2 , and the planet carrier 7 at B-B. In Figure 3, the sun gear 1, the first planetary gear 2, the planet carrier 7, O1 and O2 are the same as before. V1 represents the linear velocity of the meshing point at the 1 index circle of the sun gear (m/s), V2 represents the linear velocity of the meshing point at the 2 index circle of the first planetary gear (m/s), and V7 means the linear velocity of O2O3 around O7 (m/s) /s). ω1 represents the angular velocity of the meshing point at the 1-degree circle of the sun gear (°/s), ω2 represents the angular velocity of the meshing point at the 2-degree circle of the first planetary gear (°/s), and ω7 represents the angular velocity of O2O3 around O7 (°/s) . The velocity and angular velocity are positive in the direction shown in the figure.

According to Fig. 3, mechanical theory and kinematics theory, the linear velocity relationship model of sun gear 1, first planetary gear 2, and planet carrier 7 is established as shown in equation (1).

V ₁ =V ₇ +V ₂ (1), V1, V2 and V7 in equation (1) are the same as before.

FIG. 4 shows the transmission relationship of the second planetary gear 3, the internal gear 4, and the planet carrier 7 in the A-A section. In Figure 4, the second planetary gear 3, the internal gear 4, the planet carrier 7, V7, ω7, O3, and O7 are the same as before. V3 represents the linear velocity of the meshing point at the 3 index circle of the second planetary wheel (m/s), V4 represents the linear velocity of the meshing point at the 4 index circle of the internal gear (m/s), and ω3 represents the 3 index circle of the second planetary gear. The angular velocity of the meshing point (°/s), and ω4 represents the angular velocity (°/s) of the meshing point at the 4 index circle of the internal gear. The velocity and angular velocity are positive in the direction shown in the figure. According to FIG. 4 , mechanical theory and kinematics theory, the linear velocity relationship model of the second planetary gear 3 , the internal gear 4 , and the planet carrier 7 is established as shown in equation (2).

V ₄ =V ₇ -V ₃ (2), V3, V4 and V7 in equation (2) are the same as before.

According to the transmission principle, mechanical design theory and kinematics theory shown in Fig. 2, the known calculation formulas of the sun gear 1, the first planetary gear 2 and the second planetary gear 3 are established such as equation (3), equation (4) ) and equation (5).

V ₁ =ω ₁ ×m×Z ₁ /2 (3).

V ₂ =ω ₂ ×m×Z ₂ /2 (4).

V ₃ =ω ₂ ×m×Z ₃ /2 (5)

In equations (2) to (5), V1, V2, ω1, ω2, ω3 and V3 are the same as before, m is the gear module (mm), Z1, Z2 and Z3 are the sun gear 1, the first planetary gear 2 and the number of teeth of the second planetary gear 3, ω2=ω3.

According to the transmission principle, mechanical design theory and kinematics theory shown in FIG. 2 , the known conditional calculation formula of the internal gear 4 is established as equation (6).

V ₄ =ω ₄ ×m×Z ₄ /2=0 (6).

In equation (6), V4 and ω4 are the same as before, m is the gear module (mm), and Z4 is the number of teeth of the internal gear 4 . According to the transmission principle, mechanical design theory and kinematics theory shown in FIG. 2 , the known conditional calculation formula of the planet carrier 7 is established as equation (7).

V ₇ =ω ₇ ×m×(Z ₄ −Z ₃ )/2 (7).

In equation (7), V7 and ω7 are the same as before, m is the gear module (mm), and Z4 and Z3 are the same as before.

Simultaneous equation (1) and equation (2) are solved in combination with the known conditions of equation (3) to equation (7), and the calculation formula of the planetary gear ratio can be obtained as equation (8).

Z1, Z2, Z3 and Z4 in equation (8) are the same as before.

Select Z1, Z2, Z3 and Z4, calculate the transmission ratio according to equation (8), and compare whether the transmission ratio is in line with the use requirements (ie, the preset target value). Check, draw engineering drawings and other operations. Otherwise, the number of gear teeth of the transmission system is reselected and calculated and analyzed according to equation (8) again.

The advantages of this application: 1. A design method for planetary gear structure transmission is proposed, the principle model of planetary gear transmission, the linear velocity model and the known condition model are established, and the equation of the expression model is solved to obtain the key parameters of the transmission system; 2. A modeling method for establishing a linear velocity model is proposed based on the kinematic relationship that the linear velocity of the meshing points at the index circle of the gear is equal. This application adopts the method of establishing a kinematic model to design a transmission system, which can improve the logic, intuition, accuracy and efficiency of the design. 3. The planetary gear design method of this scheme can ensure that the designed planetary gear mechanism has high accuracy. Since the planetary gear structure is a common structure in machinery, such as automobiles, the design method of the present application can be applied in the field of ultra-precise creation of transmissions.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (2)

1. A design method of a planetary gear transmission mechanism is characterized by comprising the following steps:

s1: constructing a model of a planetary wheel mechanism, the planetary wheel mechanism comprising: a housing (5) with an internal gear (4) formed on the inner peripheral wall, a planet carrier (7), a sun gear (1), at least one planetary gear set (9) arranged on the planet carrier (7); the planetary gear set (9) comprises a first planetary gear (2) and a second planetary gear (3) which are coaxially arranged, the first planetary gear (2) is meshed with the sun gear (1), and the second planetary gear (3) is meshed with the inner gear (4); when the sun gear (1) rotates, the planet carrier (7) can be driven to rotate through the planetary gear set (9); wherein,

establishing a linear velocity relation model of the sun wheel (1), the first planet wheel (2) and the planet carrier (7): v₁＝V₇+V₂；

Establishing a second planet wheel (3), an internal gear (4) and a planet carrier (7) linear velocity relation model: v₄＝V₇-V₃；

Establishing a known conditional calculation formula of the sun wheel (1), the first planet wheel (2) and the second planet wheel (3): v₁＝ω₁×m×Z₁/2；V₂＝ω₂×m×Z₂/2；V₃＝ω₃×m×Z₃/2；

Establishing a known condition calculation formula of the internal gear (4): v₄＝ω₄×m×Z₄/2＝0；

Establishing a known condition calculation formula of the planet carrier (7): v₇＝ω₇×m×(Z₄-Z₃)/2；

S2: the gear numbers of the sun gear (1), the first planet gear (2), the second planet gear (3) and the internal gear (4) are adjusted, so that the angular speed ratio of the sun gear (1) and the planet carrier (7) is calculated according to a formula IThe target value is in accordance with a preset target value; the first formula is as follows:

wherein, ω is₁ Angular velocity, omega, of rotation of the sun gear (1)₇ Is the angular velocity, Z, of the rotation of the planet carrier (7)₁ 、Z₂ 、Z₃ And Z₄ The gear numbers of the sun gear (1), the first planet gear (2), the second planet gear (3) and the internal gear (4) are respectively; wherein, V₁ Is the linear velocity V of the meshing point at the reference circle of the sun wheel (1)₂ Is the linear speed of the meshing point at the reference circle of the first planet wheel (2), V₇ Is a linear velocity, V, about the centre line of rotation of the planet carrier (7)₃ Is the linear velocity V of the meshing point at the reference circle of the second planet wheel (3)₄ The linear speed of the meshing point at the reference circle of the internal gear (4); omega₂ Angular velocity, omega, for rotation of the first planet wheel (2)₃ Is the angular velocity, omega, of the rotation of the second planet wheel (3)₄ The angular speed of the rotation of the internal gear (4); m is the gear module.

2. A planetary gear transmission, comprising: a housing (5) with an internal gear (4) formed on the inner peripheral wall, a planet carrier (7), a sun gear (1), at least one planetary gear set (9) arranged on the planet carrier (7); the planetary gear set (9) comprises a first planetary gear (2) and a second planetary gear (3) which are coaxially arranged, the first planetary gear (2) is meshed with the sun gear (1), and the second planetary gear (3) is meshed with the inner gear (4); when the sun gear (1) rotates, the planet carrier (7) can be driven to rotate through the planetary gear set (9); wherein,

sun gear (1), first planet wheel (2), planet carrier (7) linear velocity relation model is: v₁＝V₇+V₂(ii) a The second planet wheel (3), internal gear (4), planet carrier (7) linear velocity relation model are: v₄＝V₇-V₃(ii) a The known conditional calculation formula of the sun wheel (1), the first planet wheel (2) and the second planet wheel (3) is as follows: v₁＝ω₁×m×Z₁/2；V₂＝ω₂×m×Z₂/2；V₃＝ω₃×m×Z₃2; the known conditional calculation formula of the internal gear (4) is: v₄＝ω₄×m×Z₄0 is defined as/2; the known condition calculation formula of the planet carrier (7) is as follows: v₇＝ω₇×m×(Z₄-Z₃)/2；

The angular speed ratio of the sun gear (1) and the planet carrier (7) meets a formula I; the first formula is as follows:

wherein, ω is₁ Angular velocity, omega, of rotation of the sun gear (1)₇ Is the angular velocity, Z, of the rotation of the planet carrier (7)₁ 、Z₂ 、Z₃ And Z₄ The gear numbers of the sun gear (1), the first planet gear (2), the second planet gear (3) and the internal gear (4) are respectively; wherein, V₁ Is the linear velocity V of the meshing point at the reference circle of the sun wheel (1)₂ Is the linear speed of the meshing point at the reference circle of the first planet wheel (2), V₇ Is a linear velocity, V, about the centre line of rotation of the planet carrier (7)₃ Is the linear velocity V of the meshing point at the reference circle of the second planet wheel (3)₄ The linear speed of the meshing point at the reference circle of the inner gear (4); omega₂ Angular velocity, omega, for rotation of the first planet wheel (2)₃ Is the angular velocity, omega, of the rotation of the second planet wheel (3)₄ The angular speed of the rotation of the internal gear (4); m is the gear module.

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