CN106641175A - Automobile, differential of automobile and TCU - Google Patents

Abstract

An automobile and its differential and TCU, wherein the differential includes: a differential housing; a planetary gear shaft and two planetary gears located in the differential housing, the planetary gear shafts are connected to the differential housing, The two planetary gears are respectively connected to the two ends of the planetary gear shaft; two half shafts, one end of the half shaft is fixed with a side gear, and the side gear meshes with the two planetary gears in the differential case, and the two half shafts The other ends protrude out of the differential case for connection to the two car drive wheels respectively; the planetary gear train located outside the differential case, the sun gear is used to connect to the transmission output gear, and the planet carrier is fixedly connected to the differential a housing; a first clutch for selectively connecting the transmission output gear with the planet carrier; a second clutch for selectively connecting the ring gear with the transmission housing. The structure of the differential gear in this solution is compact, the control of gear shift switching is simple, and the development and production costs are relatively low.

Description

Automobile and its differential and TCU

technical field

The invention relates to the technical field of automobiles, in particular to an automobile, a differential gear and a TCU thereof.

Background technique

At present, the automatic transmission commonly used in automobiles is a hydraulic automatic transmission (Automatic Transmission, AT). The hydraulic automatic transmission is composed of a hydraulic torque converter, a planetary gear train and a hydraulic control mechanism (such as a clutch). Among them, the hydraulic automatic transmission realizes automatic up/down shifts through complex multiple sets of planetary gear trains and multiple clutches. Therefore, the structure of the hydraulic automatic transmission is complicated, resulting in complicated control strategies for up/down shifts.

For example, an existing eight-speed hydraulic automatic transmission used in BMW and Audi cars includes a hydraulic torque converter, which has the functions of transmitting torque and clutching, but it is not yet possible to mass production. The speed change of the eight-speed hydraulic automatic transmission is realized by transmitting torque through four sets of planetary gear trains, and the processing technology is extremely demanding. In order to cooperate with the gear shifting, the eight-speed hydraulic automatic transmission is equipped with 6 sets of clutches, which also makes the gear shifting control extremely demanding.

Therefore, at present, the automatic transmission itself is mostly improved to realize switching between more gears. The automatic transmission is complicated in structure and high in cost.

Contents of the invention

The problem solved by the present invention is that most cars currently use an automatic transmission to obtain more gears, and the automatic transmission realizes automatic up/down gears through complex sets of planetary gear trains and multiple clutches, which has a complex structure and high cost.

In order to solve the above problems, the present invention provides a differential, which includes:

differential case;

The planetary gear shaft and two planetary gears located in the differential case, the planetary gear shaft is connected to the differential case in a synchronous rotation manner, and the two planetary gears are respectively connected to the differential case in a synchronous rotation manner Both ends of the planetary gear shaft;

Two half shafts, one end of the half shaft is fixed with a side gear, and the side gear meshes with the two planetary gears in the differential case, and the other ends of the two half shafts respectively extend out of the differential housing for connection to the two drive wheels of the vehicle respectively;

The planetary gear train located outside the differential case includes a ring gear, a planetary carrier, a sun gear and planetary gears. speed housing;

a first clutch for selectively connecting the transmission output gear with the planet carrier;

The second clutch is used to selectively connect the ring gear and the transmission case.

Optionally, the transmission output gear and the sun gear form a dual gear.

Optionally, the transmission output gear and the sun gear are the same gear.

The present invention also provides a TCU that cooperates with any of the differentials described above, and the cooperation between the TCU and the differential is as follows:

The TCU is used to control the disengagement or combination of the first clutch and the second clutch according to the gear to be engaged, wherein the gear to be engaged includes the forward gear to be engaged, and the number of the forward gear to be engaged is 2m, where m is the number of the transmission number of forward gears;

When the pending forward gear is a gear less than or equal to m, the TCU controls the first clutch to be disengaged and the second clutch to be engaged;

When the forward gear to be engaged is a gear greater than m, the TCU controls the first clutch to engage and the second clutch to disengage.

Optionally, the gear to be engaged further includes: a reverse gear to be engaged, the number of the reverse gear to be engaged is 2n, and n is the number of reverse gears of the transmission;

When the oncoming reverse gear is a gear less than or equal to n, the TCU controls the first clutch to be disengaged and the second clutch to be engaged;

When the oncoming reverse gear is a gear greater than n, the TCU controls the first clutch to engage and the second clutch to disengage.

Optionally, the TCU includes:

a receiving unit, configured to receive a signal to be engaged;

Storing a signal for storing the gear-to-be-engaged signal and the engagement state or disengagement state of the first clutch and the second clutch corresponding to the gear-to-be-engaged signal;

an instruction unit, configured to obtain the gear-to-be-engaged signal received by the receiving unit and the engagement state or disengagement state of the first clutch and the second clutch corresponding to the gear-to-be-engaged signal stored by the storage unit, and then An engagement command or a disengagement command is sent to the first clutch and the second clutch.

The present invention also provides an automobile, comprising: a transmission housing and a transmission output gear;

Any of the differentials described above;

Any of the TCUs mentioned above;

The sun gear is connected to the transmission output gear, the first clutch selectively connects the transmission output gear and the planet carrier, and the second clutch selectively connects the ring gear and a transmission housing.

Optionally, the transmission output gear is the final reduction and driven gear of the transmission.

Compared with the prior art, the technical solution of the present invention has the following advantages:

In the differential of this technical solution, when the first clutch is separated and the second clutch is combined, the ring gear is locked, the sun gear is active and the planet carrier is passive, and the differential has a reduction ratio K1; the _first clutch is combined and the second clutch is When separated, the sun gear and the planet carrier are connected, and the differential has a reduction ratio of K ₂ . Wherein, K ₂ is not equal to K ₁ . In this way, when any gear position of the car's transmission is transmitted to the wheels through the differential, the corresponding two reduction ratios K ₁ and K ₂ of the differential can make the wheels obtain two speeds. Therefore, the number of gears corresponding to the transmission , the number of gears that the car has can be doubled.

It should be understood that the "transmission gear" here refers to the forward gear and reverse gear of the transmission, excluding neutral gear and park gear.

The technical proposal does not require any improvement on the transmission itself, but adding a planetary gear train and two clutches to the differential can realize the switching of the automobile between more gears. Therefore, the structure of the transmission becomes simple, and the product cost is reduced. Moreover, compared with the traditional gear design scheme of the transmission, the differential of the technical scheme has a compact structure, uses fewer parts, and the control of the gear shift is simple, and the development and production costs are lower, which is different from the traditional Compared with multi-speed transmission, the product weight is also lighter.

Description of drawings

Fig. 1 is a schematic diagram of the relative positional relationship between the differential and the speed changer and between the various components in the differential according to a specific embodiment of the present invention;

Fig. 2 is a schematic diagram of the cooperative relationship between the differential and the speed changer in a specific embodiment of the present invention;

Fig. 3 is a schematic diagram of a TCU cooperating with the differential shown in Fig. 1 according to a specific embodiment of the present invention.

detailed description

In order to make the above objects, features and advantages of the present invention more comprehensible, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

It should be noted that the differential is a mechanism for adjusting the speed difference between the left and right (or front and rear) drive wheels. When the car is turning or driving on an uneven road, the differential controls the two driving wheels connected to it to roll at different speeds to ensure the pure rolling motion of the two driving wheels and avoid sliding motion. When the car is going straight, the differential controls the two drive wheels to roll at the same speed.

The technical solution proposes a new differential gear, which is used to increase the number of gears of the car and realizes the control of shifting up and down between multiple gears.

Referring to FIG. 1 , the present embodiment provides a differential 1, and the differential 1 includes: a differential housing 10;

A planetary gear shaft 13 and two planetary gears 14 located in the differential case 10, the planetary gear shaft 13 is connected to the differential case 10 in a synchronous rotation manner, and the two planetary gears 14 are respectively connected to the planetary gears in a synchronous rotation manner Both ends of the gear shaft 13;

Two half shafts 11, 12, one end of the half shaft 11, 12 is fixed with a side gear 110, 120, the side gear 110 is fixed at one end of the side shaft 11 and the side gear 120 is fixed at one end of the side shaft 12, the side shaft The gears 110, 120 mesh with two planetary gears 14 in the differential case 10, and the other ends of the two half shafts 11, 12 protrude out of the differential case 10 for connecting to the two driving wheels of the vehicle respectively. ;

The planetary gear system P located outside the differential case 10 includes a ring gear P1, a planetary carrier P2, a sun gear P3 and a planetary gear P4. The sun gear P3 is used to connect to the transmission output gear 4, and the planetary carrier P2 is fixedly connected to the differential gear. Speed housing 10;

The first clutch C1 selectively connects the planetary carrier P2 and the transmission output gear 4;

The second clutch C2 selectively connects the ring gear P1 and the transmission case 3 .

The first clutch C1 and the second clutch C2 control the reduction ratio of the differential 1, and then control the output speed and torque of the differential 1. The control method is:

The first clutch C1 is disengaged and the second clutch C2 is engaged, the connection between the planetary carrier P2 and the transmission output gear 4 is disconnected, and the ring gear P1 and the transmission case 3 are fixedly connected. At this time, the sun gear P3 is active and the planet carrier P2 is passive, the speed and torque output by the transmission output gear 4 are sequentially transmitted to the sun gear P3 and the planet carrier P2, and the planet carrier P2 drives the differential case 10 to rotate, and the differential 1 outputs speed and torque. At this time, the sun gear P3 in the differential 1 to the planetary carrier P2 realizes the reduction transmission, and the reduction ratio of the differential 1 is larger than that of the differential without the planetary gear system P. is K ₁ .

The first clutch C1 is combined and the second clutch C2 is separated. The sun gear P3 and the planetary carrier P2 are connected together. The transmission output gear 4 drives the entire planetary gear system P to rotate synchronously through the sun gear P3 and the planetary carrier P2, and is driven by the planetary carrier P2. The differential case 10 rotates. At this time, the synchronous transmission is realized from the planetary gear system P to the differential case 10, and the reduction ratio of the differential device 1 does not change compared with the reduction ratio of the differential device when the planetary gear system P is not provided. K ₂ .

Therefore, K ₁ >K ₂ , the differential gear 1 of this technical solution can switch between the reduction ratios K ₁ and K ₂ , so that under the premise of the number of gears that can be realized by the transmission, the gears that the car has Quantity doubled. For example, when the transmission is a four-speed transmission, using the differential gear 1 of the technical solution, the automobile has 8 forward gears and 2 reverse gears.

It should be noted that the transmission 2 is an automatic transmission, usually the transmission 2 includes a final reduction gear pair 20, the final reduction gear pair 20 includes a final reduction driving gear 21, and a final reduction driven gear 22 that is connected to the sun gear P3 in a synchronous rotational manner , wherein the main deceleration driving gear 21 is used as the transmission input gear, and the main deceleration driven gear 22 is used as the transmission output gear 4, and the main deceleration gear pair 20 realizes further reduction transmission to the rotating speed output by the transmission 2, and the reduction ratio is set as K;

With reference to Figure 2, taking the four-speed automatic transmission selected by the transmission 2 as an example, the cooperation mode between the differential 1 and the transmission 2 of this technical solution is explained:

1st gear: Transmission 2 is engaged in S1 gear through the hydraulic control system. At this time, the pinion system of transmission 2 is controlled by its own clutch, which has nothing to do with the first and second clutches C1 and C2 in differential 1. At the same time, in the differential 1, the first clutch C1 is hydraulically controlled to disengage and the second clutch C2 is engaged. At this time, the main deceleration driven gear 22 is driven by the main deceleration driving gear 21 to drive the sun gear P3 to rotate, while the ring gear P1 is fixedly linked with the transmission housing 3 under the action of the combination of the second clutch C2, so the planetary gear train P inputs the speed and torque from the sun gear P3 and outputs the speed and torque from the planetary carrier P2, and the planetary carrier P2 drives the differential case Body 10 rotates. When the differential case 10 rotates, the torque and speed are transmitted to the side gears 110 and 120, and then transmitted to the corresponding driving wheels respectively to drive the vehicle. The reduction ratio is R1×K×(1+K’), and R1 is the transmission 2 is output to the reduction ratio of the main reduction driving gear 21 in the 1st gear, and (1+K') is the reduction ratio of the sun gear P3 to the planetary carrier P2.

2nd gear to 4th gear: For any gear position in 2nd gear to 4th gear, please refer to the relevant content of the working principle of the first gear above. The first clutch C1 is disengaged and the second clutch C2 is engaged. At this time, in the 2nd gear, the reduction ratio is R2×K×(1+K’), R2 is the reduction ratio of the transmission 2 in the 2nd gear, and R2 is the deceleration output from the transmission to the final drive gear 21 in the 2nd gear. Ratio,; in the 3rd gear, the reduction ratio is R3×K×(1+K’), R3 is the reduction ratio that the transmission 2 outputs to the final drive gear 21 in the 3rd gear; in the 4th gear, the reduction ratio is R4 ×K×(1+K′), R4 is the speed reduction ratio output from the transmission 2 to the main reduction driving gear 21 when the transmission 2 is in 4th gear.

5th gear: Transmission 2 is engaged in S1 gear. At this time, the pinion system of transmission 2 is controlled by its own clutch, which has nothing to do with the first and second clutches C1 and C2 in differential 1. Meanwhile, in the differential 1, the first clutch C1 is engaged and the second clutch C2 is disengaged by hydraulic control. At this time, the main deceleration driven gear 22 is driven by the main deceleration driving gear 21, drives the entire planetary gear train P to rotate synchronously, and directly drives the differential case 10 to rotate through the planet carrier P2, and then transmits the torque and speed to the half shaft The gears 110 and 120 drive the vehicle, and the reduction ratio is R1×K.

6th gear: The transmission 2 is shifted into the S2 gear, and at the same time, the first clutch C1 is controlled to be engaged and the second clutch C2 is disengaged. At this time, when the vehicle is running, the speed reduction ratio is R2×K.

7th gear: The transmission 2 is shifted into the S3 gear, and at the same time, the first clutch C1 is controlled to be engaged and the second clutch C2 is disengaged. At this time, when the vehicle is running, the reduction ratio is R3×K.

8th gear: The transmission 2 is shifted into the S4 gear, and at the same time, the first clutch C1 is controlled to be engaged and the second clutch C2 is disengaged. At this time, when the vehicle is running, the reduction ratio is R4×K.

Reverse gear 1: Transmission 2 is engaged in reverse gear. At this time, the pinion system of transmission 2 is controlled by its own clutch, which has nothing to do with the first and second clutches C1 and C2 in differential 1. Meanwhile, in the differential 1, the first clutch C1 is disengaged and the second clutch C2 is engaged by hydraulic control. At this time, the speed reduction ratio when the vehicle is running is R5×K×(1+K′), and R5 is the speed reduction ratio that the transmission 2 outputs to the final drive gear 21 when the transmission 2 is in reverse gear.

Reverse gear 2: The transmission 2 is engaged in reverse gear, and at the same time, the first clutch C1 is controlled to be engaged and the second clutch C2 is disengaged. At this time, the deceleration ratio when the vehicle is running is R5×K, which is smaller than the deceleration ratio R5×K×(1+K’) at reverse gear 1, and the vehicle speed is greater than that at reverse gear 1, and reverse gear 2 The vehicle travels faster. Therefore, in a specific reverse gear driving situation, the engaged state or the disengaged state of the first clutch C1 and the second clutch C2 can be switched as required.

Therefore, when transmission 2 is a four-speed automatic transmission, with differential 1, the automobile has eight forward gear positions and two reverse gear positions, and the gear positions are doubled.

Referring to Fig. 1 and Fig. 2, the main deceleration driven gear 21 is connected with the sun gear P3, and the connection method is: the main deceleration driven gear 21 and the sun gear P2 constitute a double gear, and the central axis of the main deceleration driven gear 21 is connected to the sun gear. The central axis of the gear P2 coincides, and the final reduction driven gear 21 and the sun gear P2 are axially connected together, such as welding or integral molding.

As a modified example, the connection mode between the main deceleration driven gear 21 and the sun gear P3 can also be: when the path that the axle shaft 120 protrudes from the differential case 10 is not blocked, the main deceleration driven gear 21 and the sun gear P3 The sun gear P3 can share a gear.

The planetary gear system P is an advanced gear transmission mechanism with compact structure, small size, small mass, large bearing capacity, large transmission power range and transmission range. The sun gear P3 is located in the ring gear P1 and the two are coaxial, the planetary gear P4 is located between the sun gear P3 and the ring gear P1 and meshes with the ring gear P1 and the sun gear P3 respectively, and the number of the planetary gear P4 is at least one. The planet carrier P2 connects the rotating shafts of all planetary gears P4 and is connected to the sun gear P3. The sun gear P3 actively rotates to drive the planetary carrier P2 to revolve passively. At the same time, the planetary gear P4 is driven by the sun gear P3 to rotate and is also driven by the planetary carrier P2 to revolve. Affected by the rotation of the planetary gear P4, the output speed of the planetary carrier P2 is the same as Decrease from the input speed.

The connection between the planetary carrier P2 and the differential case 10 is: bolt connection, riveting or welding.

In addition, in the differential 1, when the wheels are going straight, the rotation speeds of the two wheels connected by the two half shafts 11, 12 are the same as the rotation speed of the differential case 10, but the rotation speeds of the three are no longer the same when the car is turning. , the planetary gear shaft 13 transmits the torque from the differential case 10 to the two planetary gears 14 to realize torque distribution, so that the wheels realize differential operation, the speed of the inner wheel decreases and the speed of the outer wheel increases.

In the differential gear 1 of the present technical solution, the hydraulic control principle of the first clutch C1 and the second clutch C2 can refer to the hydraulic control principle of the clutch of the transmission 2 , which will not be repeated here.

With reference to Fig. 1 and Fig. 3, this technical solution also provides a kind of transmission control unit (Transmission Control Unit, TCU) that cooperates with differential gear 1, and the mode of cooperation of TCU and differential gear 1 is:

The TCU is used to control the disengagement or combination of the first clutch C1 and the second clutch C2 according to the gear to be engaged, wherein the gear to be engaged includes the forward gear to be engaged, the number of the forward gear to be engaged is 2m, and m is the number of forward gears of the transmission 2 quantity;

When the forward gear to be engaged is a gear less than or equal to m, the TCU controls the first clutch C1 to be disengaged and the second clutch C2 to be engaged;

When the forward gear to be engaged is a gear greater than m, the TCU controls the first clutch C1 to be engaged and the second clutch C2 to be disengaged.

Wherein, m can be 2, 3, 4, 5 or more according to the number of forward gears to be realized by the automobile.

Further, the gear to be engaged also includes the reverse gear to be engaged, and the number of the reverse gear to be engaged is 2n, and n is the number of reverse gears of the transmission 2;

When the reverse gear to be engaged is a gear less than or equal to n, the TCU controls the first clutch C1 to be disengaged and the second clutch C2 to be engaged;

When the reverse gear to be engaged is a gear greater than n, the TCU controls the first clutch C1 to be engaged and the second clutch C2 to be disengaged.

Generally, the transmission 2 has 1 reverse gear, and at this time, with the differential 1, the car has 2 reverse gears. In other technical solutions, it is not ruled out that the transmission 2 has a plurality of reverse gears.

In order to realize the above cooperation mode, TCU includes:

a receiving unit 6, configured to receive a signal to be engaged;

The storage signal 7 is used to store the gear-to-be-engaged signal and the combined state or disengaged state of the first clutch C1 and the second clutch C2 corresponding to the gear-to-be-engaged signal;

The instruction unit 8 is used to acquire the signal to be engaged received by the receiving unit 6 and the state of engagement or disengagement of the first clutch C1 and the second clutch C2 corresponding to the signal to be engaged stored in the storage unit 7, and then send the signal to the first The clutch C1 and the second clutch C2 send an engagement command or a disengagement command. Afterwards, the first clutch C1 and the second clutch C2 perform corresponding actions.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (8)

1. A differential, characterized in that it comprises: differential case; The planetary gear shaft and two planetary gears located in the differential case, the planetary gear shaft is connected to the differential case in a synchronous rotation manner, and the two planetary gears are respectively connected to the differential case in a synchronous rotation manner Both ends of the planetary gear shaft; Two half shafts, one end of the half shaft is fixed with a side gear, and the side gear meshes with the two planetary gears in the differential case, and the other ends of the two half shafts respectively extend out of the differential housing for connection to the two drive wheels of the vehicle respectively; The planetary gear train located outside the differential case includes a ring gear, a planetary carrier, a sun gear and planetary gears. speed housing; a first clutch for selectively connecting the transmission output gear with the planet carrier; The second clutch is used to selectively connect the ring gear and the transmission case. 2. The differential according to claim 1, wherein the transmission output gear and the sun gear constitute a dual gear. 3. The differential according to claim 1, wherein the transmission output gear and the sun gear are the same gear. 4. A TCU that cooperates with the differential described in any one of claims 1 to 3, characterized in that, the cooperation between the TCU and the differential is as follows: The TCU is used to control the disengagement or combination of the first clutch and the second clutch according to the gear to be engaged, wherein the gear to be engaged includes the forward gear to be engaged, and the number of the forward gear to be engaged is 2m, where m is the number of the transmission number of forward gears; When the pending forward gear is a gear less than or equal to m, the TCU controls the first clutch to be disengaged and the second clutch to be engaged; When the forward gear to be engaged is a gear greater than m, the TCU controls the first clutch to engage and the second clutch to disengage. 5. The TCU according to claim 4, wherein the gear to be engaged further comprises: a reverse gear to be engaged, the number of the reverse gear to be engaged is 2n, and n is the number of reverse gears of the transmission; When the oncoming reverse gear is a gear less than or equal to n, the TCU controls the first clutch to be disengaged and the second clutch to be engaged; When the oncoming reverse gear is a gear greater than n, the TCU controls the first clutch to engage and the second clutch to disengage. 6. The TCU according to claim 4 or 5, characterized in that, the TCU comprises: a receiving unit, configured to receive a signal to be engaged; Storing a signal for storing the gear-to-be-engaged signal and the engagement state or disengagement state of the first clutch and the second clutch corresponding to the gear-to-be-engaged signal; an instruction unit, configured to obtain the gear-to-be-engaged signal received by the receiving unit and the engagement state or disengagement state of the first clutch and the second clutch corresponding to the gear-to-be-engaged signal stored by the storage unit, and then An engagement command or a disengagement command is sent to the first clutch and the second clutch. 7. An automobile, characterized in that it comprises: a transmission with a transmission housing and a transmission output gear; The differential described in any one of claims 1-3; The TCU according to any one of claims 4 to 6; The sun gear is connected to the transmission output gear, the first clutch selectively connects the transmission output gear and the planet carrier, and the second clutch selectively connects the ring gear and a transmission housing. 8. The automobile according to claim 7, wherein the transmission output gear is a final reduction and driven gear of the transmission.