CN206860788U - The gear transmission of three planet row six - Google Patents

Abstract

The utility model relates to the technical field of automobiles, and discloses a six-speed automatic transmission with three planetary rows, which comprises a first planetary row, a second planetary row and a third planetary row; the first sun wheel is connected with the first brake, and the first sun The wheel is connected to the second sun gear through the first clutch; the first planet carrier is fixedly connected to the second ring gear and then connected to the second brake as a whole; the second planet carrier is fixed to the third ring gear; the third sun gear is fixed , the third planet carrier is connected to the first ring gear through the third clutch; the second sun gear is fixedly connected to the power input member, and the first ring gear is fixedly connected to the power output member; the second clutch is connected to the second ring gear, the second Between the sun gear and any of the second planet carrier. The utility model adopts three clutches and two brakes, rationally connects three planetary rows, and can realize six forward gears and one reverse gear.

Description

Three planetary six-speed automatic transmission

technical field

The utility model relates to the technical field of automobiles, in particular to a three-planet six-speed automatic transmission.

Background technique

The gear train mechanism of the electronically controlled hydraulic transmission generally includes a plurality of planetary rows. The power of the engine is transmitted to the planetary gear transmission mechanism through the hydraulic torque converter for transmission and then output. The volume, weight, efficiency and carrying capacity of an automatic transmission are directly related to the planetary gear mechanism. The more the number of gears in the automatic transmission transmission system, the lower the fuel consumption of the car and the better the economy. However, with the increase in the number of gears, the number of planetary rows, the number of operating clutches and brakes are also increasing, satisfying the theoretical level. Than the design is even more difficult to achieve. People have been seeking to use fewer planetary rows, clutches and brakes to combine a planetary gear transmission mechanism with a compact structure, higher strength and better efficiency that meets the performance requirements of automobiles.

The planetary gear mechanisms of 6-speed automatic transmissions currently used in the passenger car market mainly include: Aisin, ZF, and Geely (DSI) used the Leprechaun scheme; the scheme used by Hyundai A6MF and A6LF series; the scheme used by GM 6T series ; The 6-speed solution used by Mazda Chuangchi Lantian.

The Lepelleje scheme is realized by adding a row of planetary rows on the basis of the Ravina 4-speed automatic transmission, without direct gear; however, the Lepelege scheme adopts the Ravigne structure with a double planetary gear structure, compared with a single For the planetary gear, the structure is much more complicated, which is not conducive to the compactness of the structure and increases the weight and cost. The GM and Hyundai schemes are both realized with three planetary gears, the difference lies in the position of the clutch. In the Hyundai mass-produced series A6MF and A6LF, one planetary row also uses a double planetary gear structure; the Hyundai and GM schemes both use 2 clutches and 3 brakes. The number of brakes is more than the number of clutches. The brakes are finally connected to the box through friction steel teeth. More brakes will undoubtedly increase the difficulty of manufacturing the box, and because the box The body material is generally aluminum alloy, and more brakes will undoubtedly make it difficult to achieve a lightweight design while ensuring strength. The 6-speed scheme used by Chuangchi Lantian is derived from the horizontal arrangement scheme used by ALLISON Company of the United States to match diesel engine heavy-duty trucks. The direct gear appears in the fourth gear. In terms of matching with the gasoline engine, the speed ratio configuration that can be realized is inherently insufficient. characteristic.

Utility model content

The purpose of the utility model is to provide a three-planet six-speed automatic transmission that can realize six forward gears and one reverse gear, has a more compact overall structure, and is less difficult to manufacture the transmission case.

In order to achieve the above object, the utility model provides a three-planetary six-speed automatic transmission, which includes a first planetary row, a second planetary row, a third planetary row, a first clutch, a second clutch, a third clutch, a A brake, a second brake, a power input member and a power output member; the first planetary row includes a first ring gear, a first planetary gear, a first sun gear and a first planet carrier; the second planetary row includes a first Two ring gears, a second planetary gear, a second sun gear and a second planetary carrier; the third planetary row includes a third ring gear, a third planetary gear, a third sun gear and a third planetary carrier;

The first sun gear is connected to one end of the first brake, and the first sun gear is connected to the second sun gear through the first clutch; the first planet carrier is connected to the second gear After the ring is fixedly connected, it is integrally connected with one end of the second brake; the second planet carrier is fixedly connected with the third ring gear; the third sun gear is fixed, and the third planet carrier passes through the The third clutch is connected to the first ring gear; the second sun gear is fixedly connected to the power input member, and the first ring gear is fixedly connected to the power output member;

The second clutch is connected between any two of the second ring gear, the second sun gear and the second planet carrier.

As a preferred solution, the third sun gear is fixedly connected to the transmission case.

As a preferred solution, the third sun gear is fixedly connected to the transmission case by splines or welding.

As a preferred solution, one end of the first brake is connected to the first sun gear, and the other end of the first brake is connected to the transmission case; after the first planet carrier is fixedly connected to the second ring gear The whole is connected with one end of the second brake, and the other end of the second brake is connected with the transmission case.

As a preferred solution, the first clutch, the second clutch and the third clutch are multi-plate wet clutches or dog clutches.

As a preferred solution, the first planet carrier is fixedly connected to the second ring gear by splines or welding; the second planet carrier is fixedly connected to the third ring gear by splines or welding; The second sun gear is fixedly connected to the power input member through splines or welding; the first ring gear is fixedly connected to the power output member through splines or welding.

As a preferred solution, the first planetary carrier, the second planetary carrier and the third planetary carrier are all provided with pin shafts, and the first planetary wheels are installed on the pin shafts of the first planetary carrier through bearings Above, the second planetary gear is installed on the pin shaft of the second planetary carrier through a bearing, and the third planetary wheel is installed on the pin shaft of the third planetary carrier through a bearing.

As a preferred solution, the first planetary row, the second planetary row and the third planetary row are sequentially arranged laterally.

As a preferred solution, the first clutch is arranged on a side of the first planetary row away from the second planetary row, and the third clutch is arranged on a side of the third planetary row away from the second planetary row. side, the second clutch is arranged on the side of the first planetary row away from the second planetary row or between the second planetary row and the third planetary row.

As a preferred solution, the first brake and the second brake are arranged between the first clutch and the first planetary row.

Implementation of the utility model's three-planet six-speed automatic transmission has the following advantages relative to the prior art:

1. The utility model adopts three clutches and two brakes, rationally connects three planetary rows, and can realize six forward gears and one reverse gear;

2. The number of brakes in the utility model is less than the number of clutches. Fewer brakes can not only reduce the difficulty of processing and manufacturing the transmission case, but also help reduce the weight of the case, making the entire transmission more compact; in addition , the use of more clutches will help to cut off the connection relationship between the planetary rows in a specific gear, so that the redundant planetary row does not participate in the transmission, thereby reducing the oil churning loss of the belt row and improving efficiency;

3. Setting more clutches is not only conducive to multi-speed expansion by adding planetary rows or adding more operating parts in the future, but also can nest these clutches when implementing specific structural design, so that The structure of the whole transmission is more compact.

Description of drawings

Fig. 1 is the schematic diagram of the connection structure of the three-planetary six-speed automatic transmission of the utility model embodiment one;

Fig. 2 is a schematic diagram of the first gear power transmission route of the three-planet six-speed automatic transmission according to Embodiment 1 of the utility model;

Fig. 3 is a schematic diagram of the second-speed power transmission route of the three-planetary six-speed automatic transmission according to Embodiment 1 of the utility model;

Fig. 4 is a schematic diagram of the third-speed power transmission route of the three-planet six-speed automatic transmission according to Embodiment 1 of the utility model;

Fig. 5 is a schematic diagram of the 4th gear power transmission route of the three-planetary six-speed automatic transmission according to Embodiment 1 of the utility model;

Fig. 6 is a schematic diagram of the 5th gear power transmission route of the three-planet six-speed automatic transmission according to Embodiment 1 of the present utility model;

Fig. 7 is a schematic diagram of the six-speed power transmission route of the three-planet six-speed automatic transmission according to Embodiment 1 of the utility model;

Fig. 8 is the schematic diagram of the R gear power transmission route of the three-planetary six-speed automatic transmission of the utility model embodiment one;

Fig. 9 is a schematic diagram of the connection structure of the three-planetary six-speed automatic transmission according to the second embodiment of the present invention;

Fig. 10 is a schematic diagram of the connection structure of the three-planetary six-speed automatic transmission according to the third embodiment of the present invention;

Among them, 1. The first planetary row; 11. The first ring gear; 12. The first planetary gear; 13. The first sun gear; 14. The first planet carrier; 2. The second planetary row; 21. The second ring gear ; 22, the second planetary gear; 23, the second sun gear; 24, the second planetary carrier; 3, the third planetary row; 31, the third ring gear; 32, the third planetary gear; 33, the third sun gear; 34. The third planet carrier; 4. The transmission case; B1, the first brake; B2, the second brake; C1, the first clutch; C2, the second clutch; C3, the third clutch.

detailed description

Below in conjunction with accompanying drawing and embodiment, the specific embodiment of the utility model is described in further detail. The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.

Preferred three embodiments of the utility model:

Embodiment one:

As shown in Figure 1, a three-planetary six-speed automatic transmission includes a first planetary row 1, a second planetary row 2, a third planetary row 3, a first clutch C1, a second clutch C2, and a third clutch C3 , the first brake B1, the second brake B2, the power input member and the power output member; the first planetary row 1 includes the first ring gear 11, the first planetary gear 12, the first sun gear 13 and the first planet carrier 14; The second planetary row 2 includes the second ring gear 21, the second planetary gear 22, the second sun gear 23 and the second planet carrier 24; the third planetary row 3 includes the third ring gear 31, the third planetary gear 32, the third sun gear wheel 33 and the third planet carrier 34. Specifically, the first planetary gear 12 is externally meshed with the first sun gear 13 and internally meshed with the first ring gear 11, and the first planetary gear 12 is installed on the pin shaft of the first planet carrier 14; The second sun gear 23 is externally meshed and internally meshed with the second ring gear 21, and the second planetary gear 22 is installed on the pin shaft of the second planet carrier 24; the third planetary gear 32 is externally meshed with the third sun gear 33, and Inner meshing with the third ring gear 31 , the third planetary gear 32 is installed on the pin shaft of the third planetary carrier 34 .

The first sun gear 13 is connected with one end of the first brake B1, and the first sun gear 13 is connected with the second sun gear 23 through the first clutch C1; One end of the brake B2 is connected; the second planetary carrier 24 is fixedly connected with the third ring gear 31; the third sun gear 33 is fixed, the third planetary carrier 34 is connected with the first ring gear 11 through the third clutch C3, and the second sun gear The wheel 23 is fixedly connected with the power input member, and the first ring gear 11 is fixedly connected with the power output member. It should be pointed out that since the second sun gear 23 is fixedly connected with the power input member, the first sun gear 13 can also be connected with the power input member through the first clutch C1, and can even be connected with the second sun gear 23 and the power input member. The components are connected at the same time, and the three connection methods are all equivalent technical solutions; similarly, since the first ring gear 11 is fixedly connected with the power output component, the third planet carrier 34 can also be connected with the power output component through the third clutch C3. It can even be connected with the power output member and the first ring gear 11 at the same time.

The second clutch C2 is connected between the second ring gear 21 and the second sun gear 23, specifically, the second ring gear 21 is connected to the second sun gear 23 through the second clutch C2, so that when the second clutch C2 is closed, The overall rotation of the second planetary row 2 is realized. It should also be noted that since the first planet carrier 14 is fixedly connected to the second ring gear 21, and the second sun gear 23 is fixedly connected to the power input member, there may also be multiple equivalent technical solutions, such as the second gear The ring 21 is connected to the power input member through the second clutch C2, the first planet carrier 14 is connected to the power input member through the second clutch C2, the first planet carrier 14 is connected to the second sun gear 23 through the second clutch C2, and so on.

Thus, the three-planetary six-speed automatic transmission of this embodiment can realize six forward gears and one reverse gear. The specific operation logic is shown in Table 1, wherein K is the characteristic parameter of the planetary row, and the value is equal to the number of teeth of the ring gear The ratio to the number of teeth of the sun gear, K1 corresponds to the characteristic parameter of the first planetary row 1, K2 corresponds to the characteristic parameter of the second planetary row 2, and K3 corresponds to the characteristic parameter of the third planetary row 3.

Table 1

In order to facilitate the analysis of the power flow direction of each gear, Figures 2 to 8 simplify the expression of the power flow direction of six forward gears and one R gear. The specific transmission route of each gear is analyzed as follows:

(1) 1st gear: when the third clutch C3 and the second brake B2 are closed, the speed ratio i1=(1+K2)*(1+1/K3). In this gear position, the closing of the second brake B2 makes the first planet carrier 14 and the second ring gear 21 brake, so the power transmission route of the first gear is: power input from the second sun gear 23 → second planetary gear 22 → The second planet carrier 24→the third ring gear 31→the third planet gear 32→the third planet carrier 34→the third clutch C3→the first ring gear 11 for power output, as shown in FIG. 2 .

(2) 2nd gear: when the third clutch C3 and the first brake B1 are closed, the speed ratio i1=((1+K1)(1+K2)+K3(1+K1+K2))/(K3(1+ K1)). In this gear position, the closing of the first brake B1 causes the first sun gear 13 to brake, so the second gear is divided into two power transmission routes: ① Power input from the second sun gear 23 → second planetary gear 22 → second planetary gear Carrier 24→third ring gear 31→third planetary gear 32→third planetary carrier 34→third clutch C3→first ring gear 11 for power output; ②power input from second sun gear 23→second planetary gear 22 → second ring gear 21 → first planet carrier 14 → first planetary gear 12 → first ring gear 11 for power output, as shown in FIG. 3 .

(3) 3rd gear: when the first clutch C1 and the third clutch C3 are closed, the speed ratio i1=((1+K1)(1+K2)+K3(1+K1+K2))/(K3(1+ K1+K2)). In this gear, all three planetary rows participate in the transmission, and the third gear is divided into three power transmission routes: ① Power input from the second sun gear 23 → second planetary gear 22 → second planetary carrier 24 → third ring gear 31 → third planetary gear 32 → third planetary carrier 34 → third clutch C3 → first ring gear 11 for power output; ② second sun gear 23 for power input → second planetary gear 22 → second ring gear 21 → The first planet carrier 14 → the first planetary gear 12 → the first ring gear 11 for power output; ③ the second sun gear 23 for power input → first clutch C1 → first sun gear 13 → first planetary gear 12 → second A ring gear 11 performs power output, as shown in FIG. 4 .

(4) 4th gear: when the second clutch C2 and the third clutch C3 are closed, the speed ratio i1=(1+K3)/K3). In this gear position, the closing of the second clutch C2 makes the second planetary row 2 participate in the transmission as a whole rotation, and the power transmission route of the 4th gear: the second planetary row 2 rotates as a whole for power input → the second planetary carrier 24 → the second The third ring gear 31 → the third planetary gear 32 → the third planetary carrier 34 → the third clutch C3 → the first ring gear 11 performs power output, as shown in FIG. 5 .

(5) 5th gear: when the first clutch C1 and the second clutch C2 are closed, it is a direct gear, and the speed ratio i1=1. In this gear position, the simultaneous closing of the first clutch C1 and the second clutch C2 makes the first planetary row 1 and the second planetary row 2 form a rotation and participate in transmission as a whole. The power transmission route of the 5th gear: the first planetary row 1 and The second planetary row 2 rotates as a whole for power input→the first ring gear 11 for power output, as shown in FIG. 6 .

(6) 6th gear: when the second clutch C2 and the first brake B1 are closed, it is an overdrive gear, and the speed ratio i1=K1/(1+K1). In this gear position, the closing of the second clutch C2 makes the second planetary row 2 participate in the transmission as a whole, and the closing of the first brake B1 makes the first sun gear 13 brake. The 6th gear power transmission route: by the second planetary Row 2 rotates as a whole for power input→first planet carrier 14→first planetary gear 12→first ring gear 11 for power output, as shown in FIG. 7 .

(7) R gear: when the first clutch C1 and the second brake B2 are closed, the reverse gear is realized, and the speed ratio i1=-K1. In this gear position, the closing of the second brake B2 causes the first planet carrier 14 and the second ring gear 21 to brake, and the R gear power transmission route: the second sun gear 23 input → the first clutch C1 → the first sun gear 13 → The first planetary gear 12 → The first ring gear 11 performs power output, as shown in FIG. 8 .

In this embodiment, one end of the first brake B1 is connected to the first sun gear 13, and the other end of the first brake B1 is connected to the transmission case 4; One end of the second brake B2 is connected, and the other end of the second brake B2 is connected with the transmission case 4 . In fact, the first sun gear 13 is selectively connected to the transmission case 4 through the first brake B1, and the first planet carrier 14 and the second ring gear 21 are fixedly connected to the transmission case 4 through the second brake B2 as a whole. is selectively connected, allowing for six-speed shifting functionality.

In the process of executing each gear, it is necessary to keep the third sun gear 33 fixed. If a brake is used to connect the third sun gear 33 to the transmission case 4, the brake can be used in the process of executing each gear. Keep the closed state to achieve the purpose of fixing the third sun gear 33, then, in the process of shifting gears, the brake will definitely cause a direct impact on the transmission case 4, affecting the load on the transmission case 4, so In order to avoid the direct impact of the brake on the transmission case 4 during the shifting process and improve the loading of the transmission case 4 , in this embodiment, the third sun gear 33 is fixedly connected to the transmission case 4 .

The first clutch C1, the second clutch C2 and the third clutch C3 can be multi-plate wet clutches or dog-tooth clutches: multi-plate wet clutches have the advantages of oil film protection, smooth and soft power transmission, and long service life; dog-tooth clutches It can transmit relatively large torque, and has the characteristics of simple structure and small size. Using the dog clutch can make the structure of the whole transmission more compact. In this embodiment, it is preferably a multi-plate wet clutch.

In this embodiment, the first planetary carrier 14 is fixedly connected to the second ring gear 21 through splines or welding; the second planetary carrier 24 is fixedly connected to the third ring gear 31 through splines or welding; the third sun The wheel 33 is fixedly connected to the transmission case 4 by splines or welding; the second sun gear 23 is fixedly connected to the power input member by splines or welding; the first ring gear 11 is fixed to the power output member by splines or welding fixed connection. The spline connection has the characteristics of uniform stress, good orientation, and can bear a large load, thereby ensuring the stability and reliability of the transmission during power transmission; welding can also ensure the stability and reliability of the transmission during power transmission. reliability.

In this embodiment, the first planetary carrier 14, the second planetary carrier 24 and the third planetary carrier 34 are all provided with pin shafts, the first planetary gear 12 is installed on the pin shafts of the first planetary carrier 14 through bearings, and the second The planet wheel 22 is installed on the pin shaft of the second planet carrier 24 through a bearing, and the third planet wheel 32 is installed on the pin shaft of the third planet carrier 34 through a bearing. In this way, the first planetary gear 12 , the second planetary gear 22 and the third planetary gear 32 can freely rotate on their respective planetary carriers, and can also rotate following their respective planetary carriers. Wherein, the bearing may be a rolling bearing or a sliding bearing.

The first planetary row 1, the second planetary row 2 and the third planetary row 3 are sequentially arranged horizontally. On this basis, the first clutch C1 is set on the side of the first planetary row 1 away from the second planetary row 2, the third clutch C3 is set on the side of the third planetary row 3 away from the second planetary row 2, and the second clutch C2 is arranged on the side of the first planetary row 1 away from the second planetary row 2 ; the first brake B1 and the second brake B2 are arranged between the first clutch C1 and the first planetary row 1 . Such sequential setting can optimize the structural positional relationship between each planetary carrier, ring gear, planetary carrier and operating elements (clutches, brakes), reduce the difficulty of processing and manufacturing the transmission, and reduce the mutual interference between structural components, thereby reducing the transmission. vibration and noise.

Embodiment two

As shown in Figure 9, the difference from Embodiment 1 is that the second clutch C2 is connected between the second sun gear 23 and the second planet carrier 24, that is, the second planet carrier 24 is connected to the second planet carrier 24 through the second clutch C2. The two sun gears 23 are connected, and the second clutch C2 is arranged between the second planetary row 2 and the third planetary row 3 . It is worth noting that since the second planet carrier 24 is fixedly connected to the third ring gear 31, and the second sun gear 23 is fixedly connected to the power input member, there may also be multiple equivalent technical solutions, such as the second planet carrier 24 is connected to the power input member through the second clutch C2, the third ring gear 31 is connected to the second sun gear 23 through the second clutch C2, the third ring gear 31 is connected to the power input member through the second clutch C2, and so on. When the second clutch C2 is closed, these technical solutions can achieve the technical effect of making the second planetary row 2 rotate as a whole.

The specific operation logic of the second embodiment is the same as that of the first embodiment, and the corresponding speed ratio is also the same, and the power flow direction of the second embodiment is consistent with that of the first embodiment.

Embodiment three

As shown in Figure 10, the difference from Embodiment 1 is that the second clutch C2 is connected between the second planetary carrier 24 and the second ring gear 21, that is, the second planetary carrier 24 is connected to the second planetary carrier 24 through the second clutch C2. The two ring gears 21 are connected, and the second clutch C2 is arranged between the second planetary row 2 and the third planetary row 3 . It is also worth noting that, since the second planetary carrier 24 is fixedly connected to the third ring gear 31, and the second ring gear 21 is fixedly connected to the first planetary carrier 14, there may also be multiple equivalent technical solutions, such as The second planet carrier 24 is connected to the first planet carrier 14 through the second clutch C2, the third ring gear 31 is connected to the second ring gear 21 through the second clutch C2, and the third ring gear 31 is connected to the first planet carrier through the second clutch C2. 14 connections, etc. When the second clutch C2 is closed, these technical solutions can achieve the technical effect of making the second planetary row 2 rotate as a whole.

The specific operation logic of the third embodiment is the same as that of the first embodiment, and the corresponding speed ratio is also the same, and the power flow direction of the third embodiment is consistent with that of the first embodiment.

In summary, the utility model adopts three clutches and two brakes, and rationally connects the three planetary rows to realize six forward gears and one reverse gear; in addition, the number of brakes in the utility model is less than The number of clutches and fewer brakes can not only reduce the difficulty of processing and manufacturing the transmission case 4, but also facilitate the lightweight of the case, making the entire transmission more compact; moreover, under the condition of satisfying the same number of speed ratios , fewer brakes can obviously improve the utilization rate of each brake, thus making the whole transmission more compact; again, using more clutches will help to cut off the connection relationship between the planetary rows in a specific gear, making redundant The planetary row does not participate in the transmission, thereby reducing the oil churning loss of the belt row and improving efficiency; setting more clutches is not only conducive to multi-speed expansion by adding planetary rows or adding more operating parts in the future, but also in the specific implementation. When designing the structure, these clutches can also be nested, so that the structure of the entire transmission is more compact.

The above are only preferred embodiments of the present utility model, and it should be pointed out that for those of ordinary skill in the art, without departing from the technical principles of the present utility model, some improvements and replacements can also be made. These improvements and replacements It should also be regarded as the protection scope of the present utility model.

Claims (10)

1. A three-planetary six-speed automatic transmission, characterized in that: comprising the first planetary row, the second planetary row, the third planetary row, the first clutch, the second clutch, the third clutch, the first brake, the second Brake, power input member and power output member; the first planetary row includes the first ring gear, the first planetary gear, the first sun gear and the first planet carrier; the second planetary row includes the second ring gear, the first Two planetary gears, a second sun gear and a second planetary carrier; the third planetary row includes a third ring gear, a third planetary gear, a third sun gear and a third planetary carrier; The first sun gear is connected to one end of the first brake, and the first sun gear is connected to the second sun gear through the first clutch; the first planet carrier is connected to the second gear After the ring is fixedly connected, it is integrally connected with one end of the second brake; the second planet carrier is fixedly connected with the third ring gear; the third sun gear is fixed, and the third planet carrier passes through the The third clutch is connected to the first ring gear; the second sun gear is fixedly connected to the power input member, and the first ring gear is fixedly connected to the power output member; The second clutch is connected between any two of the second ring gear, the second sun gear and the second planet carrier. 2. The three-planet six-speed automatic transmission according to claim 1, characterized in that: the third sun gear is fixedly connected to the transmission case. 3. The three-planetary six-speed automatic transmission according to claim 2, characterized in that: the third sun gear is fixedly connected to the transmission case by splines or welding. 4. The three-planetary six-speed automatic transmission according to claim 1, characterized in that: one end of the first brake is connected to the first sun gear, and the other end of the first brake is connected to the transmission case ; The first planet carrier is fixedly connected to the second ring gear and then integrally connected to one end of the second brake, and the other end of the second brake is connected to the transmission case. 5. The three-planetary six-speed automatic transmission according to any one of claims 1-4, characterized in that: the first clutch, the second clutch and the third clutch are multi-plate wet clutches or Dog clutch. 6. The three-planetary six-speed automatic transmission according to any one of claims 1-4, characterized in that: the first planet carrier is fixedly connected to the second ring gear by splines or welding; The second planet carrier is fixedly connected to the third ring gear by splines or welding; the second sun gear is fixedly connected to the power input member by splines or welding; the first ring gear It is fixedly connected with the power output member through splines or welding. 7. The three-planetary six-speed automatic transmission according to any one of claims 1-4, characterized in that: the first planetary carrier, the second planetary carrier and the third planetary carrier are all equipped with The pin shaft, the first planet wheel is installed on the pin shaft of the first planet carrier through the bearing, the second planet wheel is installed on the pin shaft of the second planet carrier through the bearing, and the third planet The wheel is mounted on the pin shaft of the third planet carrier through bearings. 8. The three-planetary six-speed automatic transmission according to any one of claims 1-4, characterized in that: the first planetary row, the second planetary row and the third planetary row are sequentially arranged horizontally . 9. The three-planetary six-speed automatic transmission according to claim 8, wherein the first clutch is arranged on the side of the first planetary row away from the second planetary row, and the third clutch set on the side of the third planetary row away from the second planetary row, the second clutch is set on the side of the first planetary row away from the second planetary row or the second planetary row and between the third planet row. 10. The three-planetary six-speed automatic transmission according to claim 9, wherein the first brake and the second brake are arranged between the first clutch and the first planetary row.