CN103953698B - A kind of electrically driven (operated) planetary transmission - Google Patents

Abstract

A kind of electrically driven (operated) planetary transmission, it includes housing, input link, output link, Simpson compound planetary row, two torque transmitters and four interconnecting components；Centered by Simpson compound planetary is arranged, left is the input link of drive system, and right is the output link of power train, and two torque transmitters are brake, and side by side near housing, above-mentioned each component is respectively positioned in housing；The present invention has the series of advantages such as simple in construction is tight, transmission efficiency is high, good manufacturability, manufacturing expense are low, gear shift is steady, maneuvering performance is good, it is used in electric motor car carrying out transmission work, not only save space, and transmission efficiency is high, meet motor operating characteristic, drive characteristic can be made more preferable.

Description

An electric drive planetary gear transmission

technical field

The invention provides an electrically driven planetary gear transmission, which is a two-speed planetary gear transmission mechanism and belongs to the technical field of electric vehicle automatic transmissions.

Background technique

With the increasing development of electric vehicles, the requirements for the performance of the transmission system are getting higher and higher. Since the traditional fixed ratio transmission has high requirements on the driving motor and cannot balance economy and power, the development of multi-speed automatic transmission for electric vehicles has become an irresistible trend. Because the planetary gear transmission mechanism has the characteristics of large transmission ratio, small size, large load capacity and stable operation, it is widely used in automatic transmissions. Therefore, the layout scheme design of the planetary row becomes the first prerequisite for the development of the automatic transmission.

Patent CN203098765U discloses an arrangement scheme including two sets of planetary gear sets at the front and rear. In the scheme, the front sun gear is connected to the output shaft of the motor, the front and rear sun gears are coaxial and the rear sun gear is fixed, the rear inner planetary gear meshes with the rear sun gear and the rear outer planetary gear, and the final power is output by the rear ring gear. The two clutches are respectively arranged on the planetary carrier between the front planetary carrier and the rear inner planetary wheel and on the ring gear between the front ring gear and the rear outer planetary wheel. Two brakes are used to lock the front ring gear and lock the front planet carrier respectively.

The scheme disclosed in the patent CN202872557U includes two single-row 2K-H planetary gear transmission systems. The first-stage reduction is realized by relying on the front row planetary gear transmission system to fix the front row ring gear, and the power is transmitted from the front row sun gear to the front row planets. rack output. The second gear is completed by the rear planetary gear transmission system, the clutch C1 realizes the combination or separation of the rear sun gear and the rear planet carrier, the brake B1 realizes the fixation and separation of the rear ring gear and the box, and finally the rear row Star frame output power.

The disclosed scheme of the patent CN201795003U is as follows: the input shaft drives the planetary carrier through the first clutch, and drives the sun gear through the second clutch, one end of which is connected to the output shaft of the motor. At the same time, the output gear is fixed coaxially with the planetary carrier, it drives the driving gear of the differential through the intermediate shaft, and the ring gear is fixedly connected with the transmission case.

The electric vehicle automatic transmission technology has just started, but its small size, compact structure and improved motor efficiency make its birth inevitable. From the current research, it can be seen that there is still a lot of research space for the planetary row arrangement scheme of the two-speed automatic transmission of electric vehicles.

Contents of the invention

(1. Purpose

The object of the present invention is to provide an electrically driven planetary gear transmission, which overcomes the deficiencies of the prior art, and is a two-speed transmission with a compact structure and is convenient for driving an electrically driven vehicle.

(2) Technical solution

The present invention is an electrically driven planetary gear transmission, which includes a casing, an input member, an output member, a Simpson compound planetary row, two torque transmission devices, and four interconnected members. Among them, the positional relationship between them is: taking the Simpson compound planetary row as the center, the input member of the transmission system on the left, the output member of the transmission system on the right, and the two torque transmission devices are brakes, which are side by side close to the housing. All the above-mentioned components are located in the casing.

The casing is the shell of the planetary gear transmission, which is fixed and used to accommodate and support other components of the transmission. Its shape and structure are determined by the design layout, and there is no fixed form.

The input member is the input shaft of the planetary gear transmission, through which the output speed and torque of the electric motor are input to the planetary gear transmission, and the input member is unique, and is located in front of the Simpson compound planetary row.

The output member is the output shaft of the planetary gear transmission, through which the rotational speed and torque of the planetary gear transmission are output to the follow-up transmission shaft, and the output member is the only one, located behind the Simpson compound planetary row.

The Simpson compound planetary row is a compound planetary gear mechanism, which consists of a sun gear assembly, a front row planet carrier, a front row ring gear and rear row planet carrier, a rear row ring gear and front and rear rows Composed of star gears; the sun gear assembly meshes with the front and rear planetary gears respectively, the front ring gear meshes with the front planetary gears, the rear ring gear meshes with the rear planetary gears, the front ring gear and the rear planetary carrier are fixed couplet.

The first interconnecting member is a connecting shaft, which fixedly connects the sun gear assembly and the input shaft of the Simpson compound planetary row.

The second interconnecting member is a connecting shaft, which fixedly connects the rear ring gear and the output shaft of the Simpson compound planetary row.

The third interconnecting member is a connecting shaft, which fixedly connects the front ring gear and the rear planet carrier of the Simpson compound planetary row with the first torque transmission device.

The fourth interconnecting member is a connecting shaft that fixedly connects the front planetary carrier of the Simpson compound planetary row with the second torque transmitting device.

The two torque transmission devices are both wet friction engagement elements, and the corresponding two components are connected together through the engagement of different torque transmission devices. Two torque-transmitting devices can be selectively locked to temporarily connect two components.

The first torque-transmitting device, which is selectively lockable, connects the front ring gear and the rear planet carrier of the Simpson compound planetary row to the housing.

The second torque-transmitting device, which is selectively lockable, connects the front planetary carrier of the Simpson compound planetary row to the housing.

Wherein, the transmission scheme involved in the present invention realizes the automatic transmission function by controlling two torque transmission devices to generate two forward gears.

Among them, the above-mentioned Simpson-type composite planetary row is composed of two simple minus-signed planetary rows, sharing a sun gear assembly, wherein the front ring gear and the rear-row planetary carrier are fixedly connected to form a component; in the above-mentioned Simpson-type composite planetary row The gears involved in are all helical toothed.

Wherein, the first and second torque transmission devices are wet friction disc brakes. The size of the brake needs to be calculated according to the output torque of the matched motor, and the present invention does not limit specific applicable models and specifications.

The structural principle and working overview of the present invention are as follows: when all the torque transmission devices are in the disengaged state, the degree of freedom of the planetary gear mechanism is 2, and there is no power transmission between the input member and the output member; when the first torque transmission device is in the locked state , the front ring gear and the rear planet carrier assembly of the Simpson compound planetary row are fixed, the degree of freedom of the planetary gear mechanism is reduced to 1, there is power transmission between the input and output members, and the ratio of the speed of the input member to the output member is one gear gear ratio.

When the second torque transmission device is in the locked state, the front planetary carrier of the Simpson compound planetary row is fixed, the degree of freedom of the planetary gear mechanism is reduced to 1, there is power transmission between the input and output members, and the rotation speed of the input member and the output member is the same. The ratio is the second gear ratio.

(3) Advantages

The Simpson type has a series of advantages such as simple and compact structure, high transmission efficiency, good manufacturability, low manufacturing cost, smooth shifting, and good maneuverability. Using it for transmission work on an electric vehicle not only saves space, but also has high transmission efficiency, conforms to the working characteristics of the motor, and can make the transmission characteristics better.

Description of drawings

Fig. 1 is a schematic structural view of a specific embodiment of an electrically driven planetary gear transmission according to the present invention;

reference sign

0 housing; 1 first interconnection member; 2 second interconnection member; 3 third interconnection member; 4 fourth interconnection member;

S1 front sun gear; S2 rear sun gear; R1 front ring gear; R2 rear ring gear;

A1 front planetary carrier; A2 rear planetary carrier; G1 front planetary gear; G2 rear planetary gear;

P1 front negative planetary row; P2 rear negative planetary row; IN input shaft; OUT output shaft;

B1 first torque transmitting device; B2 second torque transmitting device.

detailed description:

The following description is merely exemplary in nature and is in no way intended to limit the application or uses of the invention.

The present invention is an electrically driven planetary gear transmission, which is a second-speed electric drive transmission with a planetary gear structure, which includes a housing 0; an input member is an input shaft IN; an output member is an output shaft OUT; a Simpson compound planet Row; first interconnecting member 1; second interconnecting member 2; third interconnecting member 3; fourth interconnecting member 4; first torque transmitting device B1; second torque transmitting device B2. The relationship between them is: taking the Simpson compound planetary row as the center, the left is the input member of the transmission system, the right is the output member of the transmission system, and the two torque transmission devices are brakes, which are side by side close to the housing 0. The components are all located in the housing 0.

The housing 0 is determined according to the specific engineering implementation, and its main function is to support various components of the invention.

First, the two speed electric drive transmission embodiment of the present invention has a permanent mechanical linkage arrangement on a Simpson compound planetary row.

Referring first to FIG. 1, the transmission includes an input shaft IN, a Simpson compound planetary row, a housing 0, an output shaft OUT, a first torque transmitting device B1, a second torque transmitting device B2, a first interconnecting member 1, and a second interconnecting member. The connection member 2 , the third interconnection member 3 , the fourth interconnection member 4 , and the Simpson compound planetary row in the embodiment of the present invention are as follows.

The Simpson compound planetary row is composed of the negative planetary row P1 in the front row and the negative planetary row P2 in the rear row, which includes the front and rear sun gears S1 and S2, the front and rear planetary gears G1 and G2, the front and rear row Ring gear R1, R2, front and rear planet carrier A1, A2. The front and rear sun gears S1 and S2 are fixedly connected to the input shaft IN through the first interconnection member 1; the rear ring gear R2 is fixedly connected to the output shaft OUT through the second interconnection member 2; the front ring gear R1 and the rear planetary The carrier A2 is fixedly connected with the first torque transmission device B1 through the third interconnection member; the front planetary carrier A1 is fixedly connected with the second torque transmission device B2 through the fourth interconnection member.

The first torque transmission device B1 selectively connects the front ring gear R1 and the rear planetary carrier A2 of the Simpson compound planetary row with the transmission housing 0 . The second torque transmitting device B2 selectively connects the front planetary carrier A1 of the Simpson compound planetary row with the transmission housing 0 .

The input shaft IN is directly connected to an electric motor (not shown). The output shaft OUT is connected to a final transmission unit or a transfer case or the like (not shown).

The shifting operation of this embodiment will be described with reference to the following list-shift logic diagram and the transmission ratio of each gear. The transmission is capable of transmitting torque from an input shaft IN to an output shaft OUT in two forward speed or torque ratios. The transmission or torque ratio for each forward gear is achieved by a combination of the torque transmitting devices (shift elements). Table One shows a truth table for combinations of torque transmitting mechanisms that are activated or engaged to achieve a gear state. As shown in Table One, an "x" indicates that the particular torque transmitting device (shift element) is engaged to achieve the desired gear state. Among them, the Simpson compound planetary row can be regarded as a negative planetary gear set with a fixed transmission ratio of -3.68 composed of the front sun gear S1, the front planetary gear G1, the front ring gear R1, and the planet carrier A1, and the rear sun gear S2, The rear planetary gear G2, the rear planetary carrier A2 and the rear ring gear R2 form a negative planetary gear set with a transmission ratio of -3.45. The transmission ratios of each gear of the transmission shown in Table 1 are obtained.

The foregoing description of the operation and gear states of a two-speed transmission assumes that: first, all shift elements specifically mentioned in a given gear state are disengaged; and second, shifts between adjacent gear states (i.e. During a change of gear state), a shift element that is engaged in both gear states will remain engaged.

The aspects of the invention are merely exemplary in nature and variations that do not depart from the invention are intended to be within the scope of the invention. Such variations are considered without departing from the spirit and scope of the invention.

The calculation method of transmission scheme transmission ratio is as follows:

Calculation formula of first gear transmission ratio: i1=i01

Second gear transmission ratio calculation formula i2=-i01*i02/(1-i01-i02)

The symbols in the formula are explained as follows:

i1 first gear ratio

i2 second gear ratio

i01 Simpson compound planetary row is equivalent to the fixed transmission ratio of the negative planetary gear set in the front row

i02 Simpson compound planetary row equivalent rear negative planetary gear set fixed transmission ratio

Table I

B1 B2 transmission ratio 1 x -3.68 2 x -1.56

Claims (1)

1. an electrically driven (operated) planetary transmission, it is characterised in that: it contains housing, input link i.e. power shaft, output link i.e. output shaft, Simpson compound planetary row, the first interconnecting component, the second interconnecting component, the 3rd interconnecting component, the 4th interconnecting component, the first torque transmitter and the second torque transmitter；Relation between them is: centered by Simpson compound planetary is arranged, left is the input link of drive system, and right is the output link of drive system, and two torque transmitters are brake, side by side near housing；

Housing function is to support every component of electrically driven (operated) planetary transmission；

Simpson compound planetary row is made up of front-seat negative sign planet row and heel row negative sign planet row, and it includes forward and backward sun gear, forward and backward rows of planetary gear, forward and backward toothrow circle, forward and backward seniority among brothers and sisters carrier；Forward and backward sun gear is connected by the first interconnecting component and power shaft are fixing；Rear ring gear is connected by the second interconnecting component and output shaft are fixing；Front-seat gear ring and heel row planet carrier are fixedly linked by the 3rd interconnecting component and the first torque transmitter；Front-seat planet carrier is fixedly linked by the 4th interconnecting component and the second torque transmitter；

Front-seat gear ring and heel row planet carrier that Simpson compound planetary is arranged by the first torque transmitter optionally connect with case of transmission；The front-seat planet carrier that Simpson compound planetary is arranged optionally is connected by the second torque transmitter with case of transmission；

Power shaft is directly connected to motor；Output shaft is connected to final gear unit；

Moment of torsion can be delivered to output shaft from power shaft with two forward gear gear ratios or torque ratio by this variator；Combine by some in torque transmitter, it is thus achieved that the gear ratio of each forward gear or torque ratio；Table one is the combination truth table being activated or engaging to realize the torque-transmitting mechanisms of shifting state；In table one, "×" represents this concrete torque transmitter and is engaged to realization expectation shifting state；Wherein Simpson compound planetary row regards as by front sun gear, front-seat planetary gear, front-seat gear ring, front-seat planet carrier composition fixed drive ratio is the negative sign planetary gearsets of-3.68 and by rear sun gear, heel row planetary gear, heel row planet carrier and the negative sign planetary gearsets that rear ring gear composition gear ratio is-3.45 collectively form；

Transmission scheme gear ratio calculation method is as follows:

One gear gear ratio calculation formula: i1=i01

Two gears gear ratio calculation formula: i2=-i01*i02/ (1-i01-i02)

In formula, symbol description is as follows:

I1 mono-keeps off gear ratio；

I2 bis-keeps off gear ratio；

The front-seat negative sign planetary gearsets fixed drive ratio of i01 Simpson compound planetary row's equivalence；

I02 Simpson compound planetary row's equivalence heel row negative sign planetary gearsets fixed drive ratio；

Table one

B1 B2 Gear ratio 1 X -3.86 2 X -1.56

。