阅读说明：本技术 一种电动汽车用两档减速器 (Two-gear speed reducer for electric automobile ) 是由 朱国浩 黄福军 于 2021-09-17 设计创作，主要内容包括：本发明公开了一种电动汽车用两档减速器,用于汽车行驶过程中的换挡,包括双离合器、输入轴组、太阳轮组、双联行星轮和驱动轴,电动汽车的电机输出轴连接双离合器,所述离合器连接输入轴组,输入轴组连接太阳轮组,太阳轮组通过双联行星轮,所述双联行星轮设置在行星架上,行星架连接电动汽车的驱动轴,电动汽车电机提供的动力依次通过离合器、太阳轮、行星轮和行星架传递给驱动轴,动力传递路线因离合器接合方式不同而不同,从而完成一挡、两档和空挡的切换。本发明执行动作迅速且易精确控制,档位平滑切换,无动力中断,换挡舒适性高；结构简单紧凑；无主减速结构,可重量和尺寸小,减轻了汽车的负荷,传动效率高。(The invention discloses a two-gear speed reducer for an electric automobile, which is used for gear shifting in the automobile running process and comprises a double clutch, an input shaft group, a sun wheel group, a duplex planet wheel and a driving shaft, wherein the motor output shaft of the electric automobile is connected with the double clutch, the clutch is connected with the input shaft group, the input shaft group is connected with the sun wheel group, the sun wheel group passes through the duplex planet wheel, the duplex planet wheel is arranged on a planet carrier, the planet carrier is connected with the driving shaft of the electric automobile, power provided by a motor of the electric automobile is transmitted to the driving shaft through the clutch, the sun wheel, the planet wheel and the planet carrier in sequence, and power transmission routes are different due to different clutch engagement modes, so that the switching of a first gear, a second gear and a neutral gear is completed. The invention has the advantages of rapid execution action, easy and accurate control, smooth gear switching, no power interruption and high gear shifting comfort; the structure is simple and compact; the automobile has no main speed reducing structure, small weight and size, reduced load of the automobile and high transmission efficiency.)

1. The utility model provides a two grades of reduction gears for electric automobile for the car shifts of in-process that traveles, the reduction gear includes the casing, its characterized in that still includes double clutch (2), input shaft group, sun gear group, pair planet wheel (5) and drive shaft (9), double clutch (2) are connected in electric automobile's motor output shaft (1), input shaft group is connected in double clutch (2), input shaft group connects sun gear group, sun gear group passes through pair planet wheel, pair planet wheel sets up on planet carrier (8), electric automobile's drive shaft (9) are connected in planet carrier (8).

2. The two-speed reducer for electric vehicles according to claim 1, wherein the double clutch (2) comprises a first clutch (C1) and a second clutch (C2), the input shaft set comprises a first input shaft (12) and a second input shaft (11), the sun gear set comprises a first sun gear (3) and a second sun gear (10), one end of the first input shaft (12) is rigidly connected with the second clutch (C2), and the other end is sleeved with the first sun gear (3); the first input shaft (12) is a hollow shaft and is sleeved on the second input shaft (11), two ends of the second input shaft (11) extend out of two ends of the first input shaft (10), one end of the second input shaft is rigidly connected with the first clutch (C1), and the other end of the second input shaft is sleeved with the second sun gear (10).

3. The two-gear reducer for the electric automobile according to claim 1, wherein the double planetary gear (5) comprises a large planetary gear (4) and a small planetary gear (7) which are mounted on a planetary carrier, the large planetary gear (4) is meshed with the first sun gear (3) on the inner side of the planetary carrier (8), the small planetary gear (7) is meshed with the second sun gear (10) on the inner side of the planetary carrier (8), the large planetary gear (4) and the small planetary gear (7) are coaxially and rigidly connected, the small planetary gear (7) is meshed with an inner gear ring (6) on the outer side of the planetary carrier (8), and the inner gear ring (6) is rigidly connected with the inner wall of the shell.

4. The two-gear speed reducer for the electric automobile according to claim 2, wherein the first input shaft (12) is rigidly connected with the second clutch (C2) through a spline, and the first sun gear (3) is sleeved on the first input shaft (12) and is rigidly connected with the first input shaft; the second input shaft (11) is rigidly connected with the first clutch (C1) through a spline, and the second sun gear (10) is sleeved on the second input shaft (11) and is rigidly connected with the second input shaft.

5. Two-speed reducer for electric vehicles according to claim 1, characterized in that the planet carrier (8) is rigidly connected to a drive shaft (9), the drive shaft (9) being arranged coaxially to the motor output shaft (1).

6. The two-speed reducer for electric vehicles according to claim 1, wherein the motor output shaft (1) is rigidly connected to the double clutch (2) by splines.

7. The two-speed reducer for electric vehicles according to claim 1, wherein the double clutch (2) is a wet multiple-plate double clutch, and its driving mechanism is a hydraulic driving mechanism.

8. The two-speed reducer for electric vehicles according to claim 1, wherein when the first clutch (C1) is engaged, the electric vehicle is in the first gear, when the second clutch (C1) is engaged, the electric vehicle is in the second gear, and when neither the first clutch (C1) nor the second clutch (C1) is engaged, the electric vehicle is in neutral.

9. The two-speed reducer for electric vehicles according to claim 8, wherein the number of teeth of the first sun gear (3) is Z₁The number of teeth of the second sun gear (10) is Z₂The number of teeth of the large planet wheel (4) is Z₃The number of teeth of the small planet wheel (7) is Z₅The number of teeth of the inner gear ring (6) is Z₆；a＝Z₆/Z₂，b＝Z₆/Z₅，c＝Z₃/Z₁；

The speed ratio of the first gear is as follows: i.e. i₁＝1+a；

The speed ratio of the second gear is as follows: i.e. i₂＝1+b·c。

Technical Field

The invention relates to an electric automobile driving device, in particular to a two-gear speed reducer for an electric automobile.

Background

The common speed reducer in the electric drive system of the existing electric automobile comprises a first-speed-ratio speed reducer (namely, a single-speed-ratio speed reducer) and a two-gear speed reducer, and compared with the single-speed-ratio speed reducer, the pure electric automobile can greatly improve the power performance of the whole automobile such as acceleration performance, climbing performance, highest speed and the like by matching the two-gear speed reducer on the premise of reducing the output torque of a motor. And the driving system is matched with the two-gear speed reducer, so that the comprehensive efficiency of the assembly can be improved. Therefore, various technical schemes of two-gear speed reducers suitable for electric automobiles are proposed in the prior art.

The technical scheme of the existing two-gear speed reducer mainly comprises the following three types:

the Mechanical two-gear Automatic speed reducer (AMT) has simple structure, high Transmission efficiency and low cost, but the driving force interruption during gear shifting influences the gear shifting comfort;

an Automatic two-gear speed reducer (AT) saves a hydraulic torque converter, realizes two-gear functions through different combinations of a planetary gear Transmission mechanism, a clutch, a brake, a one-way clutch and other parts, but has complex structure, high manufacturing difficulty and high maintenance cost.

The double-Clutch two-gear speed reducer (DCT) can realize the gear shifting without interrupting the driving force, but is not suitable for driving an electric automobile with coaxial output due to the parallel shaft structure, and has larger occupied space.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a two-gear speed reducer which is simple and compact in structure and can realize smooth gear shifting.

The technical scheme is as follows: the invention relates to a two-gear speed reducer for an electric automobile, which is used for shifting gears in the running process of the automobile and comprises a double clutch, an input shaft group, a sun wheel group, a duplex planet wheel and a driving shaft.

The double clutches comprise a first clutch and a second clutch, the input shaft group comprises a first input shaft and a second input shaft, the sun gear group comprises a first sun gear and a second sun gear, one end of the first input shaft is rigidly connected with the second clutch, and the other end of the first input shaft is sleeved with the first sun gear; the first input shaft is a hollow shaft and is sleeved on the second input shaft, the second input shaft extends out of two ends of the first input shaft, one end of the second input shaft is rigidly connected with the first clutch, and the other end of the second input shaft is sleeved with a second sun gear.

The planet wheel set comprises a large planet wheel and a small planet wheel which are arranged on a planet carrier, the large planet wheel is meshed with a first sun wheel on the inner side of the planet carrier, the small planet wheel is meshed with a second sun wheel on the inner side of the planet carrier, the large planet wheel and the small planet wheel are coaxial and rigidly connected, the small planet wheel is meshed with an inner gear ring on the outer side of the planet carrier, and the inner gear ring is rigidly connected with the inner wall of the shell. The first input shaft is rigidly connected with the second clutch C2 through a spline, and the first sun gear is sleeved on the first input shaft and is rigidly connected with the first input shaft; the second input shaft is rigidly connected with the first clutch C1 through a spline, and the second sun gear is sleeved on the second input shaft and is rigidly connected with the second input shaft. The planet carrier is rigidly connected to a drive shaft, which is arranged coaxially with the output shaft. The output shaft of the motor is rigidly connected with the double clutch through a spline. The double clutches are wet multi-plate double clutches, and the driving mechanism is a hydraulic driving mechanism.

When the first clutch is engaged, the electric automobile is located at a first gear, when the second clutch is engaged, the electric automobile is located at a second gear, and when the first clutch is not engaged with the second clutch, the electric automobile is in a neutral gear.

The number of teeth of the first sun gear is Z₁The number of teeth of the second sun gear is Z₂The number of teeth of the large planet wheel is Z₃The number of teeth of the small planet wheel is Z₅And the number of teeth of the inner gear ring is Z₆；a＝Z₆/Z₂，b＝Z₆/Z₅，c＝Z₃/Z₁；

The speed ratio of the first gear is as follows: i.e. i₁＝1+a；

The speed ratio of the second gear is as follows: i.e. i₂＝1+b·c。

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: the double-clutch executing action is rapid and easy to control accurately, gear switching is smooth, no power interruption is caused, and the gear shifting comfort is high; the coaxially arranged two-gear transmission has a more compact structure and small weight and size, and is beneficial to saving the arrangement space in an automobile; the main speed reducing structure is omitted, the load of the automobile is reduced, and the transmission efficiency is high.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining the attached drawings.

As shown in fig. 1, the two-gear speed reducer for the electric vehicle according to the present invention includes a dual clutch 2, a first sun gear 3, a large planet gear 4, a double planet gear 5, an inner gear ring 6, a small planet gear 7, a planet carrier 8, a driving shaft 9, a second sun gear 10, a second input shaft 11, and a first input shaft 12, wherein the dual clutch 2 is rigidly connected to a motor output shaft 1 of the electric vehicle through a spline; the first input shaft 12 is rigidly connected with the second clutch C2 through a spline, and the first sun gear 3 is sleeved on the first input shaft 12 and is rigidly connected with the first input shaft;

the second input shaft 11 is rigidly connected with the first clutch C1 through a spline, and the second sun gear 10 is sleeved on the second input shaft 11 and is rigidly connected with the second input shaft; the duplex planet wheel 5 comprises a large planet wheel 4 and a small planet wheel 7, and is arranged on a planet carrier 8, and the large planet wheel 4 is rigidly connected with the small planet wheel 7; the large planet wheel 4 is meshed with the first sun wheel 3 at the inner side of the planet carrier 8; the small planet wheel 7 is meshed with the second sun gear 10 at the inner side of the planet carrier 8, and the small planet wheel 7 is meshed with the inner gear ring 6 at the outer side of the planet carrier 8; the inner gear ring 6 is rigidly connected to the shell of the reducer through connecting structures such as an external spline and the like arranged on the outer ring of the inner gear ring, is used as a fixing element in a planet row transmission system, is engaged with the planet wheel and restrains one degree of freedom in two degrees of freedom in transmission. The planet carrier 8 is rigidly connected to a drive shaft 9, the drive shaft 9 being arranged coaxially with the motor output shaft 1. The double clutches 2 are wet multi-plate double clutches and adopt hydraulic drive mechanisms.

The number of teeth of the first sun gear is Z₁The number of teeth of the second sun gear is Z₂The number of teeth of the large planet wheel is Z₃The number of teeth of the small planet wheel is Z₅And the number of teeth of the inner gear ring is Z₆；a＝Z₆/Z₂，b＝Z₆/Z₅，c＝Z₃/Z₁；

The speed ratio of the first gear is as follows: i.e. i₁＝1+a；

The speed ratio of the second gear is as follows: i.e. i₂＝1+b·c。

The two-gear speed reducer comprises the following three working modes:

a first gear: the first clutch C1 is engaged, the first input shaft and the first sun gear rotate freely, power is transmitted to the second sun gear through the second input shaft, the second sun gear is input and then passes through the small planet gear, and the power is output from the driving shaft through the planet carrier after being decelerated;

a second gear: the second clutch C2 is engaged, the second input shaft and the second sun gear rotate freely, power is transmitted to the first sun gear through the first input shaft, the first sun gear is input, passes through the large planetary gear and the small planetary gear, and is output from the driving shaft through the planetary carrier after being decelerated;

neutral position: the clutches C1 and C2 are all separated, and the first sun gear, the second sun gear and the planet carrier rotate arbitrarily.