A structure of a planetary gear reducer with a large transmission ratio, a calculation of a transmission ratio, and a parameter determination method

Abstract

The application provides a structure of a planetary gear reducer with a large transmission ratio, a transmission ratio calculation method and a parameter determination method. The structure is based on reverse thinking of a closed planetary transmission structure theory and a differential gear theory in a planetary gear transmission. The fixed shaft gear train in the closed planetary transmission principle is organically combined with the planetary gear train gear parameters. Thus, the reduction ratio of the planetary reducer can be improved without increasing the number of the reducer stages or even reducing the transmission stages of the reducer. Moreover, the axial dimension of the reducer can be shortened. The volume of the reducer is smaller than that of a common planetary gear reducer with the same transmission ratio. The reducer can be applied to occasions with a large transmission ratio and a large torque output, such as joint reducers of industrial robots, large torque electric wrenches and the like.

Description

Technical Field

[0001] The present invention relates to the field of speed reducers, and in particular to a structure of a planetary gear speed reducer with a large transmission ratio, a transmission ratio calculation method and a parameter determination method. Background Art

[0002] As a mechanical transmission device, the reduction gear is widely used in many fields, and the planetary reducer is a universal reducer with a flexible structure and various application forms. However, a comprehensive review of relevant technologies shows that the current planetary reducers have the following problems: the first-stage reduction ratio of the planetary reduction mechanism is not large, and a multi-stage combination is required in actual use. In large transmission ratio applications, the transmission chain is long, resulting in a large axial dimension and low efficiency. It is not convenient to use in occasions with space constraints, such as industrial robot joint reducers, portable high-torque power tools, etc. Due to the limitations of the planetary reducer structure, it cannot fully play its role. Summary of the Invention

[0003] The present invention relates to a structure of a planetary gear reducer with a large transmission ratio, a transmission ratio calculation method and a parameter determination method. The structure is simple and the manufacturing is convenient, and a higher transmission ratio and motion accuracy can be obtained.

[0004] The present invention adopts the following technical solutions: a planetary gear reducer structure with a large transmission ratio, wherein the front and rear parts thereof are respectively provided with a front-stage fixed-axis reduction mechanism and a rear-stage planetary reduction mechanism, wherein the front-stage fixed-axis reduction mechanism mainly comprises a front fixed-axis wheel carrier, a front fixed-axis gear, a front driving gear and an internal gear ring, and the rear-stage planetary reduction mechanism mainly comprises a rear planetary wheel carrier, a rear planetary gear and a rear sun gear and an internal gear ring, the front fixed-axis wheel carrier is integrated with the housing, the housing is combined with the rear planetary wheel carrier through a bearing, the rear planetary wheel carrier can rotate in the housing, an internal gear ring is provided inside the housing, the middle part of the rear planetary wheel carrier is integrated with the output shaft, the front driving gear is located at the front-stage The middle position of the fixed axis reduction mechanism, the rear sun gear is located in the middle position of the rear stage planetary reduction mechanism, the input shaft passes through the front fixed axis wheel carrier, the front driving gear, the rear sun gear and the rear planetary wheel carrier from front to rear, the input shaft is fixed with the front driving gear and the rear sun gear and rotates synchronously, the input shaft is supported by the front bearing located in the middle of the front fixed axis wheel carrier and the rear bearing located in the middle of the rear planetary wheel carrier, the front driving gear and the rear sun gear are coaxially arranged, the number of teeth of the rear sun gear and the number of teeth difference between the front driving gear is 2, the front driving gear is meshed with the front fixed axis gear, the rear sun gear is meshed with the rear planetary gears, and the front fixed axis gear and the rear planetary gears are both meshed with the inner gear ring.

[0005] Furthermore, the front driving gear and the rear sun gear are concentrically distributed.

[0006] Furthermore, the input shaft, the front driving gear and the rear sun gear are integrated into one body.

[0007] Furthermore, the difference between the number of teeth of the rear sun gear and the number of teeth of the front driving gear is 2.

[0008] Furthermore, the tooth difference between the front fixed axis gear 4 and the rear planetary gear 9 is 1.

[0009] Furthermore, a friction-reducing washer is provided between the front fixed axis gear and the rear planetary gear.

[0010] Furthermore, a friction reducing plate is provided between the end face of the inner gear ring and the end faces of the supporting bearings of the front fixed-axis wheel carrier and the outer ring of the rear planetary wheel carrier to isolate them.

[0011] Furthermore, the front fixed shaft gear and the rear planetary gear are mainly composed of the superposition of gear I and gear II. The center of the end face of gear I is provided with a groove and a pin shaft I is pressed into the corresponding position in the groove. The end face of gear II opposite to gear I is provided with a protruding pin shaft II. A retaining spring is provided between gear I and gear II, and the two end holes of the retaining spring are movably connected with the pin shaft I and the pin shaft II respectively. When gear I and gear II are assembled, the circumferential direction of the gear teeth are staggered by an angle, and rotate around the front gear shaft or the rear gear shaft under the action of the elastic force of the retaining spring. When the front fixed shaft gear is respectively engaged with the front driving gear and the internal gear ring, and when the rear planetary gears are respectively engaged with the rear sun gear and the internal gear ring, the opposite sides of gear I and gear II are pressed against the teeth of the front driving gear and the internal gear ring and the teeth of the rear sun gear and the internal gear ring under the action of the elastic force of the retaining spring, so that there is no side clearance during transmission, eliminating the backlash of the reducer transmission chain.

[0012] The present invention also discloses a method for calculating the transmission ratio of a planetary gear reducer with a large transmission ratio. First, according to the theoretical design formula of the planetary gear reducer:

[0013] n1+a*n2=(1+a)n3

[0014] Where: n1 is the sun gear speed, n2 is the ring gear speed, n3 is the planet carrier speed, a is the ratio of the number of teeth of the ring gear to the number of teeth of the sun gear, a=Z3 / Z1, Z3 is the number of teeth of the ring gear, Z1 is the number of teeth of the sun gear;

[0015] When the planet carrier is fixed, n3=0, n1=-a*n2, n2=-n1 / a,

[0016] Assume that the parameters of the front group of planetary mechanism are without superscript and the parameters of the rear group are with superscript.

[0017] The two sets of planetary gear elements at the front and rear:

[0018] When the sun gear and ring gear are fixedly connected,

[0019] n1 = n1', take n1 as the system input speed;

[0020] n2 = n2';

[0021] n3 = 0, that is, the front group planetary carrier is fixed;

[0022] n3', the system output speed;

[0023] Inference: the front group is n1 + a * n2 = (1 + a) * n3;

[0024] The rear group is n1' + a' * n2' = (1 + a') * n3';

[0025] The general formula of the reduction ratio of the combined planetary reduction mechanism is obtained as

[0026] i = n1 / n3' = (1 + a') / (1 - a' / a);

[0027] According to the general formula and the setting conditions of the project, it can be deduced that

[0028] i = (Z1' + Z3) / (Z1' - Z1);

[0029] When the number of teeth of the inner gear ring in the front and rear groups is the same, i = (Z3 + Z1') / tooth difference;

[0030] According to the planetary gear train structure design theory, it can be deduced that when the sun gear tooth difference is 2 and the planetary gear tooth difference is 1, the structure can be simplified to achieve the most.

[0031] Therefore, the transmission ratio i of the project is (Z3 + Z1') / 2;

[0032] That is, the transmission ratio of the project is i = (the number of teeth of the inner gear ring + the number of teeth of the sun gear) / 2.

[0033] The application also discloses a method for determining basic parameters of a gear train in actual use of a planetary gear reducer with a large transmission ratio, which comprises the following steps:

[0034] Step one, input the number of teeth of the gear ring and the number of teeth of the front driving gear;

[0035] Step two, according to the design theory of the planetary reducer, the sum of the number of teeth of the gear ring and the number of teeth of the sun gear must be an integer multiple of the number of planetary gears. Calculate Zs, which is the sum of the number of teeth of the gear ring and the number of teeth of the driving gear, that is, Zs = the number of teeth of the gear ring + the number of teeth of the front driving gear;

[0036] Step three, from the prime numbers of 3, 4 and 5, respectively, take the value of X(j) according to the sequence number j

[0037] Step 4: Determine whether Zs is divisible by X(j):

[0038] If Zs cannot be divided by x(j), then continue to take the next value x(j+1) and perform the calculation repeatedly until a value that can be divided by x(j) is obtained. x(j) is determined as the number of fixed axis gears (4);

[0039] Step 5: Calculate Zp, Zp = number of teeth on the rear sun gear + number of teeth on the ring gear + 2;

[0040] Step 6: Take out the prime numbers above 3, 4, and 5 and assign them to y(k) according to the sequence number k.

[0041] Step 7: Determine whether Zp is divisible by y(k):

[0042] If Zp cannot be divided by y(k), then continue to take the next value of y(k+1) and repeat the calculation until a value that can be divided by y(k) is obtained, and y(k) is determined as the number of the next stage planetary gears;

[0043] Step 8: Calculate the transmission ratio according to the transmission ratio calculation method of the planetary gear reducer with a large transmission ratio. The system transmission ratio is i, and the system transmission ratio i=Zp / 2;

[0044] Furthermore, the number of planetary gears is preferably X={3, 4, 5, 7...}.

[0045] The present invention has the following beneficial effects: after adopting the above technical scheme, the present invention is based on the reverse thinking of the closed planetary transmission structure theory and the gear differential theory in the planetary gear transmission, and organically combines and associates the fixed-axis gear train in the closed planetary transmission principle with the gear parameters of the planetary gear train. The present invention can increase the transmission ratio of the reducer and improve the reduction ratio of the planetary reducer without increasing the number of reducer stages or even reducing the number of transmission stages of the reducer. It can also shorten the axial dimension of the reducer, and its volume is smaller than that of the two-stage planetary gear transmission, thereby improving the transmission efficiency. It can be applied to many occasions. For example, in high-torque situations, ordinary gears can be used to replace backlash-free planetary gears to obtain higher structural strength; zero backlash can be achieved in low-load situations with high precision requirements to achieve precise transmission function. In addition, the present invention also has a compact structure, greater torque-increasing performance and a wide transmission ratio range. From a manufacturing perspective, it is easier to apply to practical applications than the large transmission ratio and large torque characteristics of the RV reducer currently widely used in robots. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 It is a structural schematic diagram of the present invention.

[0048] Figure 2 It is a schematic diagram of the end surface structure of the front fixed axis gear and the rear planetary gear of the present invention.

[0049] Figure 3 It is a side structural schematic diagram of the front fixed axis gear and the rear planetary gear of the present invention.

[0050] Figure 4 It is a schematic diagram of the combination of the front fixed axis gear and the rear planetary gear of the present invention.

[0051] Figure 5 This is a schematic diagram of the present invention.

[0052] Figure 6 Schematic diagram of the flow of parameters in the transmission ratio calculation of the present invention. DETAILED DESCRIPTION

[0053] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0054] exist Figure 1 、 Figure 2 and Figure 4The present invention provides a planetary gear reducer structure with a large transmission ratio, wherein the front and rear parts thereof are respectively provided with a front-stage fixed-axis reduction mechanism and a rear-stage planetary reduction mechanism, wherein the front-stage fixed-axis reduction mechanism mainly comprises a front fixed-axis wheel carrier 2, a front fixed-axis gear 4, a front driving gear 3 and an internal gear ring 7, and the rear-stage planetary reduction mechanism mainly comprises a rear planetary wheel carrier 17, a rear planetary gear 9 and a rear sun gear 15 and an internal gear ring 7, the front fixed-axis wheel carrier 2 is integrated with the housing 8, the housing 8 is combined with the rear planetary wheel carrier 17 through a bearing 10, the rear planetary wheel carrier 17 can rotate in the housing 8, an internal gear ring 7 is provided inside the housing 8, the middle part of the rear planetary wheel carrier 17 is integrated with the output shaft 16, the front driving gear 3 is located in the middle of the front-stage fixed-axis reduction mechanism, and the rear sun gear 15 is located in the middle of the rear-stage planetary reduction mechanism. The input shaft 1 passes through the front fixed-axis wheel carrier 2, the front driving gear 3, the rear sun gear 15 and the rear planetary wheel carrier 17 from front to rear. The input shaft is fixed to the front driving gear 3 and the rear sun gear 15 and rotates synchronously. The input shaft 1 is supported by the front bearing 14 located in the middle of the front fixed-axis wheel carrier 2 and the rear bearing 13 located in the middle of the rear planetary wheel carrier 17. The front driving gear 3 and the rear sun gear 15 are coaxially arranged. The number of teeth of the rear sun gear 15 is 2 more than that of the front driving gear 3. The front driving gear 3 is meshed with the front fixed-axis gear 4, and the rear sun gear 15 is meshed with the rear planetary gear 9. The front fixed shaft gear 4 and the rear planetary gears 9 are both meshed with the internal gear ring 7. The front driving gear 3 and the rear sun gear 15 of this embodiment are concentrically distributed. The input shaft, the front driving gear and the rear sun gear of this embodiment are integrated. The number of teeth of the rear sun gear 15 of this embodiment is 2 more than the number of teeth of the front driving gear 3. The number of teeth of the front fixed shaft gear 4 of this embodiment is 1 more than the number of teeth of the rear planetary gears 9. A friction-reducing washer 18 is provided between the front fixed shaft gear 4 and the rear planetary gears 9 of this embodiment. A friction-reducing plate 19 is provided between the end face of the internal gear ring 7 of this embodiment and the end face of the support bearing 10 of the outer ring of the front fixed shaft wheel carrier 2 and the rear planetary wheel carrier 17. The front fixed shaft gear 4 and the rear planetary gear of this embodiment are isolated. The wheel 9 is mainly composed of a superposition of gear I20 and gear II21. The center of the end face of the gear I20 is provided with a groove and a pin shaft I22 is pressed into the corresponding position in the groove. The end face of the gear II21 opposite to the gear I20 is provided with a protruding pin shaft II23. A retaining spring 24 is provided between the gear I20 and the gear II21. The two end holes of the retaining spring 24 are movably connected with the pin shaft I22 and the pin shaft II23 respectively. When the gear I20 and the gear II21 are assembled, the circumferential direction of the gear teeth is staggered by an angle and rotates around the outer ring of the front support bearing 6 or the rear support bearing 11 under the action of the elastic force of the retaining spring 24. The front gear shaft 5 and the rear gear shaft 12 are connected to the gear 4 or the gear 9 by the front support bearing 6 or the rear support bearing 11 respectively.When the front fixed shaft gear 4 is respectively engaged with the front driving gear 3 and the internal gear ring 7, and the rear planetary gear 9 is respectively engaged with the rear sun gear 3 and the internal gear ring 7, the opposite side surfaces of gear I 20 and gear II 21 are pressed against the gear teeth of the front driving gear 3 and the internal gear ring 7 and the gear teeth of the rear sun gear 13 and the internal gear ring 7 under the action of the elastic force of the retaining spring 24, so that there is no side clearance during transmission, and the backlash of the reducer transmission chain is eliminated.

[0055] The use process of the planetary gear reducer with large transmission ratio of the present invention is as follows: Figure 3 and Figure 5 In the figure, the rotation of the input shaft 1 will drive the front driving gear 3 and the coaxial rear sun gear 15 to rotate synchronously. The front driving gear 3 meshes with the front fixed shaft gear 4, which meshes with the internal gear ring 7. The internal gear ring 7 rotates around the input shaft 1 under the action of the input shaft 1 in the opposite direction. The rear planetary gears 9 mesh with the rear sun gear 15 and the internal gear ring 7. At the gear meshing point, they are subject to two forces: the force of the rear sun gear 15, which is fixed to the input shaft 1 and rotates synchronously with it, and the force of the internal gear ring 7, which moves in the opposite direction of the input shaft 1. Due to the difference in the number of teeth on the two sun gears and the number of teeth on the two planetary gears, the two forces on the rear planetary gears 9 are not equal. Under the action of the normal velocity difference at the point of action, the rear planetary gears 9 rotate about their own axis with V not equal to zero. Their axis will revolve in the direction of movement of the duplex input gear shaft 1, driving the rear planetary gear carrier 17 and the output shaft 16 to rotate and output, thereby achieving speed change.

[0056] The present invention also provides a method for calculating the transmission ratio of a planetary gear reducer with a large transmission ratio. First, according to the theoretical design formula of the planetary gear reducer:

[0057] n1+a*n2=(1+a)n3

[0058] Where:

[0059] n1 — sun gear speed,

[0060] n2 —— ring gear speed,

[0061] n3 — planet carrier speed,

[0062] a——Ratio of the number of teeth of the ring gear to the sun gear a=Z3 / Z1,

[0063] Z3——Number of teeth in the ring gear,

[0064] Z1——number of sun gear teeth,

[0065] When the planet carrier is fixed, n3=0, n1=-a*n2, n2=-n1 / a,

[0066] Assume that the parameters of the front group of planetary mechanism are without superscript and the parameters of the rear group are with superscript.

[0067] The two sets of planetary gear elements at the front and rear:

[0068] When the sun gear and ring gear are fixedly connected,

[0069] n1=n1', take n1 as the system input speed;

[0070] n2=n2';

[0071] n3=0, that is, the front planet carrier is fixed;

[0072] n3', is the system output speed;

[0073] Corollary: The first group is n1+a*n2 =(1+a)*n3;

[0074] The latter group is n1'+a'*n2' =(1+a')*n3';

[0075] The general formula for the reduction ratio of the planetary reduction mechanism after combination is obtained as follows:

[0076] i=n1 / n3'=(1+a') / (1-a' / a);

[0077] From the general formula, according to the conditions set in this project, it can be deduced that

[0078] i=(Z1'+Z3) / (Z1'-Z1);

[0079] When the number of teeth in the front and rear gear rings is the same, i=(Z3+Z1') / tooth difference;

[0080] According to the design theory of planetary gear train structure, it can be deduced that the structure can be realized in the simplest way when the sun gear tooth difference is 2 and the planet gear tooth difference is 1;

[0081] Therefore, the design transmission ratio of this project is i=(Z3+Z1') / 2;

[0082] That is, the transmission ratio of this project is i=(number of teeth on the inner ring gear + number of teeth on the sun gear) / 2.

[0083] The present invention illustrates this calculation method:

[0084] Assume that the number of teeth on the reducer ring gear is Z3=68, and the number of teeth on the sun gear is Z2=22.

[0085] According to the calculation of the present invention, the transmission ratio is i=(68+22) / 2=45;

[0086] If a typical planetary reduction mechanism is used, the reduction ratio calculation formula of the planetary reducer is:

[0087] i=(1+Z3 / Z1)

[0088] The secondary planetary reduction gear ratio is i=(1+68 / 20)*(1+68 / 22)=18

[0089] Therefore, the present invention can greatly improve the reduction ratio of the planetary reducer without increasing the number of reducer stages and only slightly changing the transmission structure components.

[0090] exist Figure 6 The present invention also provides a method for determining parameters in the transmission ratio calculation of a planetary gear reducer with a large transmission ratio, comprising the following steps: Step 1: Input the number of teeth of the ring gear and the number of teeth of the preceding driving gear 3; Step 2: According to the design theory of planetary reducers, the sum of the number of teeth of the ring gear and the number of teeth of the sun gear must be an integer multiple of the number of planetary gears. Calculate Zs, where Zs is the sum of the number of teeth of the ring gear 7 and the driving gear 3, i.e., Zs = number of teeth of the ring gear + number of teeth of the driving gear; Step 3: From the prime numbers 3, 4, and 5 or greater, assign the values ​​to X(j) according to the sequence number j; Step 4: Determine whether Zs is divisible by X(j):

[0091] If Zs cannot be divided by x(j), continue to take the next value x(j+1) and perform the calculation repeatedly until a value that can be divided by x(j) is obtained. Determine x(j) as the number of fixed axis gears (4); Step 5, calculate Zp, Zp = the number of teeth of the rear stage sun gear + the number of teeth of the ring gear + 2; Step 6, take the prime numbers of 3, 4, and 5 or more and assign them to y(k) according to the sequence number k.

[0092] Step 7: Determine whether Zp is divisible by y(k): If Zp is not divisible by y(k), continue to take the next value y(k+1) and repeat the calculation and judgment until a value that is divisible by y(k) is obtained. y(k) is determined as the number of the subsequent planetary gears 9;

[0093] Step 8: According to the above method of calculating the transmission ratio of the planetary gear reducer with a large transmission ratio

[0094] Calculate the transmission ratio, the system transmission ratio is i, the system transmission ratio i=Zp / 2; the number of planetary gears in the present invention is preferably X={3, 4, 5, 7...}, and in this embodiment, X=3 is preferred.

[0095] Without limitation to this, any changes or substitutions that are not conceived through creative work should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection defined in the claims.

Claims

1. A method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio, characterized in that: The following steps are involved: Step 1: Input the number of teeth of the ring gear and the number of teeth of the front driving gear (3); Step 2: According to the design theory of planetary reducers, the sum of the number of teeth of the ring gear and the number of teeth of the sun gear must be an integer multiple of the number of planetary gears. Calculate Zs, which is the sum of the number of teeth of the ring gear (7) and the front driving gear (3), that is, Zs = the number of teeth of the ring gear + the number of teeth of the front driving gear; Step 3: Take out the prime numbers above 3, 4, and 5 and assign them to X(j) according to the sequence number j. Step 4: Determine whether Zs is divisible by X(j): If Zs cannot be divided by x(j), continue to take the next value of x(j+1) and perform loop calculation and judgment; Until a value that is divisible by x(j) is obtained, x(j) is determined as the number of fixed axis gears (4); Step 5: Calculate Zp, Zp = number of teeth on the rear sun gear + number of teeth on the ring gear + 2; Step 6: Take out the prime numbers above 3, 4, and 5 according to the sequence number k and assign them to y(k); Step 7: Determine whether Zp is divisible by y(k): If Zp cannot be divided by y(k), then continue to take the next value of y(k+1) and perform cyclic calculation and judgment until a value that can be divided by y(k) is obtained, and y(k) is determined as the number of the subsequent planetary gears (9); Step 8: Calculate the transmission ratio according to the transmission ratio calculation method of a planetary gear reducer with a large transmission ratio, where the system transmission ratio is i, i=Zp / 2; The number of planetary gears is X={3,4,5,7...}; A planetary gear reducer structure with a large transmission ratio, wherein the front and rear parts thereof are respectively provided with a front-stage fixed-axis reduction mechanism and a rear-stage planetary reduction mechanism, wherein the front-stage fixed-axis reduction mechanism mainly comprises a front fixed-axis wheel carrier (2), a front fixed-axis gear (4), a front driving gear (3) and an inner gear ring (7), and the rear-stage planetary reduction mechanism mainly comprises a rear planetary wheel carrier (17), a rear planetary gear (9), a rear sun gear (15) and an inner gear ring (7), wherein the front fixed-axis wheel carrier (2) is integrated with a housing (8), and the housing (8) is combined with the rear planetary wheel carrier (17) through a bearing (10), and the rear planetary wheel carrier (17) can rotate in the housing (8), and an inner gear ring (7) is provided inside the housing (8), and the middle part of the rear planetary wheel carrier (17) is integrated with the output shaft (16), the front driving gear (3) is located in the middle position of the front-stage fixed-axis reduction mechanism, and the rear sun gear (15) is located in the middle position of the rear-stage planetary reduction mechanism; The input shaft (1) passes through the front fixed axis wheel frame (2), the front driving gear (3), the rear sun gear (15) and the rear planetary wheel frame (17) in sequence from front to rear. The input shaft is fixed to the front driving gear (3) and the rear sun gear (15) and rotates synchronously. The input shaft (1) is supported by a front bearing (14) located in the middle of the front fixed axis wheel frame (2) and a rear bearing (13) located in the middle of the rear planetary wheel frame (17). The front driving gear (3) and the rear sun gear (15) are coaxially arranged. The number of teeth of the rear sun gear (15) differs by 2 teeth from the number of teeth of the front driving gear (3). The front driving gear (3) is meshed with the front fixed axis gear (4), the rear sun gear (15) is meshed with the rear planetary gear (9), and the front fixed axis gear (4) and the rear planetary gear (9) are both meshed with the inner gear ring (7).

2. The method for determining the basic parameters of the gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 1 is characterized by: The front driving gear (3) and the rear sun gear (15) are concentrically distributed.

3. The method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 2, characterized in that The input shaft, the front driving gear and the rear sun gear are integrated into one body.

4. The method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 3 is characterized in that The number of teeth of the rear sun gear (15) differs from the number of teeth of the front driving gear (3) by 2 teeth.

5. The method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 4 is characterized in that The number of teeth of the front fixed shaft gear (4) differs from the number of teeth of the rear planetary gear (9) by one tooth, and a friction-reducing washer (18) is provided between the front fixed shaft gear (4) and the rear planetary gear (9).

6. The method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 5, characterized in that A friction reducing plate (19) is provided between the end face of the inner gear ring (7) and the end faces of the support bearings (10) of the outer rings of the front fixed-axis wheel carrier (2) and the rear planetary wheel carrier (17).

7. The method for determining basic parameters of a gear train during actual use of a planetary gear reducer with a large transmission ratio according to claim 6, characterized in that The front fixed axis gear (4) and the rear planetary gear (9) are mainly composed of gear I (20) and gear II (21) superimposed. A groove is provided at the center of the end face of gear I (20) and a pin shaft I (22) is pressed into the corresponding position in the groove. The end face of gear II (21) opposite to gear I (20) is provided with a protruding pin shaft II (23). A retaining spring (24) is provided between gear I (20) and gear II (21). The two end holes of the retaining spring (24) are respectively movably connected to the pin shaft I (22) and the pin shaft II (23). When gear I (20) and gear II (21) are assembled, the gear teeth are staggered in the circumferential direction. Angle, and rotate around the front gear shaft (5) or the rear gear shaft (12) under the action of the elastic force of the retaining spring (24), when the front fixed shaft gear (4) is respectively engaged with the front driving gear (3) and the internal gear ring (7), and when the rear planetary gear (9) is respectively engaged with the rear sun gear (3) and the internal gear ring (7), the opposite sides of gear I (20) and gear II (21) are pressed against the gear teeth of the front driving gear (3) and the internal gear ring (7) and the gear teeth of the rear sun gear (13) and the internal gear ring (7) under the action of the elastic force of the retaining spring (24), so that there is no side clearance during transmission, and the backlash of the reducer transmission chain is eliminated.

Images