CN114738478B

CN114738478B - Shifting fork control method and device of double-clutch automatic gearbox

Info

Publication number: CN114738478B
Application number: CN202210351898.1A
Authority: CN
Inventors: 涂安全; 李星; 罗贤虎; 徐洪伟; 侯金
Original assignee: Anhui Jianghuai Automobile Group Corp
Current assignee: Anhui Jianghuai Automobile Group Corp
Priority date: 2022-04-02
Filing date: 2022-04-02
Publication date: 2023-04-07
Anticipated expiration: 2042-04-02
Also published as: CN114738478A

Abstract

The application discloses shift fork control method and device of a double-clutch automatic gearbox, and the shift fork control method comprises the following steps: determining a first correction coefficient of a pressure control proportional valve and a second correction coefficient of a flow control proportional valve corresponding to a target gear in a gear shifting request according to a current driving mode and a current gear shifting type; obtaining the corrected initial pressure and the corrected initial flow; calculating the current target pressure of the pressure control proportional valve and the current target flow of the flow control proportional valve; and controlling the shifting fork corresponding to the target gear in the gear shifting request to move according to the current target pressure and the current target flow, so as to realize the gear engaging operation of the target gear. This application accelerates or slows down the speed that the fender position combines as required according to the travelling speed of driving mode and the type automatic adjustment shift fork of shifting, improves the driving experience under different driving mode and the different type of shifting.

Description

Shifting fork control method and device of double-clutch automatic gearbox

Technical Field

The application relates to the technical field of automobiles, in particular to a shifting fork control method and device of a double-clutch automatic gearbox.

Background

The double-clutch automatic gearbox (DCT for short) is one of the mainstream automatic gearboxes at home and abroad at present. A structural schematic diagram of a 6-speed double-clutch automatic gearbox is shown in figure 1, and seven driving gears are provided, namely 1/2/3/4/5/6 and R gear. The shifting fork and the synchronizer are the most direct operating elements for the DCT gearbox to complete gear switching, the synchronizer is fixedly connected with the shifting fork, and when the gears are shifted, hydraulic pistons at two ends of the shifting fork move under the action of pressure oil to push the synchronizer to be embedded into the combined teeth of the gear gears, so that the synchronization of the rotating speed of the gear shifting gears and the rotating speed of the synchronizer gear sleeve is realized, and the gear engagement is realized. For example, as shown in fig. 1, when the shift fork of the synchronizer 2 is controlled to push left, the 6-gear is engaged; if the shifting fork pushes towards the middle, a neutral gear is engaged; push right, combine 2 grades.

In the existing double-clutch automatic gearbox, the shifting fork is controlled to move only according to different gears and the oil temperature of the gearbox. With the increase of the demands of consumers on the driving function and the driving experience of the vehicle, different driving modes and different gear shifting types appear, and the demands of different driving modes and different gear shifting types cannot be met according to the existing shifting fork control method.

Disclosure of Invention

The application provides a shifting fork control method and device of a double-clutch automatic gearbox, the moving speed of a shifting fork is automatically adjusted according to a driving mode and a gear shifting type, the speed of combining gears is accelerated or slowed down according to needs, and the driving experience under different driving modes and different gear shifting types is improved.

The application provides a shift fork control method of a double-clutch automatic gearbox, which comprises the following steps:

responding to a gear shifting request, and acquiring a current driving mode and a current gear shifting type;

determining a first correction coefficient of a pressure control proportional valve and a second correction coefficient of a flow control proportional valve corresponding to a target gear in a gear shifting request according to a current driving mode and a current gear shifting type;

correcting the initial pressure of the pressure control proportional valve during gear combination according to a first correction coefficient to obtain corrected initial pressure, and correcting the initial flow of the flow control proportional valve during gear combination according to a second correction coefficient to obtain corrected initial flow;

calculating the current target pressure of the pressure control proportional valve and the current target flow of the flow control proportional valve;

and controlling the shifting fork corresponding to the target gear in the gear shifting request to move according to the current target pressure and the current target flow, so as to realize the gear engaging operation of the target gear.

Preferably, the first correction coefficient and the second correction coefficient of each shift type in the standard driving mode are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the same shift type in the economy driving mode;

the first correction coefficient and the second correction coefficient of each gear shifting type in the power driving mode are respectively larger than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type in the standard driving mode.

Preferably, in the same driving mode, the first correction coefficient and the second correction coefficient of the dynamic downshift are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the dynamic upshift;

in the same driving mode, the first correction coefficient and the second correction coefficient of the dynamic upshift are respectively larger than or equal to the first correction coefficient and the second correction coefficient of the coasting upshift and the coasting downshift.

Preferably, calculating the current target pressure of the pressure control proportional valve includes:

acquiring the current state of the gearbox and the real-time position of a shifting fork corresponding to a target gear in the gear shifting request;

determining the pressure change gradient of the pressure control proportional valve when the gears are combined according to the current state of the gearbox, the target gear and the real-time position of the shifting fork;

inputting the corrected initial pressure and pressure change gradient into an integral calculator to obtain output data of the integral calculator;

determining the maximum pressure limit value of the pressure control proportional valve when gears are combined according to the current oil temperature of the gearbox;

the smaller of the maximum pressure limit and the output data of the integral calculator is taken as the current target pressure.

Preferably, the initial pressure of the pressure control proportional valve when the gear combination is determined according to the current oil temperature of the gearbox and the target gear.

Preferably, the initial flow of the flow control proportional valve when the gears are combined is determined according to the current state of the gearbox, the target gear and the real-time position of the shifting fork corresponding to the target gear.

Preferably, calculating the current target flow of the flow control proportional valve comprises:

determining the maximum flow limit value of the flow control proportional valve when gears are combined according to the current oil temperature of the gearbox;

and taking the smaller of the maximum flow limit value and the corrected initial flow as the current target flow.

The application also provides a shifting fork control device of the double-clutch automatic gearbox, which comprises an information acquisition module, a correction coefficient determination module, a correction module, a current pressure and flow calculation module and a control module;

the information acquisition module is used for responding to the gear shifting request and acquiring a current driving mode and a current gear shifting type;

the correction coefficient determining module is used for determining a first correction coefficient of a pressure control proportional valve and a second correction coefficient of a flow control proportional valve corresponding to a target gear in the gear shifting request according to the current driving mode and the current gear shifting type;

the correction module is used for correcting the initial pressure of the pressure control proportional valve during gear combination according to a first correction coefficient to obtain corrected initial pressure, and correcting the initial flow of the flow control proportional valve during gear combination according to a second correction coefficient to obtain corrected initial flow;

the current pressure and flow calculation module is used for calculating the current target pressure of the pressure control proportional valve and the current target flow of the flow control proportional valve;

the control module is used for controlling the shifting fork corresponding to the target gear in the gear shifting request to move according to the current target pressure and the current target flow, and achieving the gear engaging operation of the target gear.

Preferably, in the standard driving mode, the first correction coefficient and the second correction coefficient of each shift type are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the same shift type in the economical driving mode;

in the power driving mode, the first correction coefficient and the second correction coefficient of each gear shifting type are respectively larger than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type in the standard driving mode.

Other features of the present application and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application.

FIG. 1 is a schematic diagram of a DCT;

FIG. 2 is a hydraulic control schematic of a shift execution module of the DCT;

fig. 3 is a flowchart of a shifting fork control method of a dual clutch automatic transmission according to the present application;

FIG. 4 is a logic diagram for determining a current target pressure for a pressure controlled proportional valve provided herein;

FIG. 5 is a logic diagram for determining a current target flow rate of the proportional flow control valve provided by the present application;

fig. 6 is a structural diagram of a shift fork control device of a dual clutch automatic transmission according to the present application.

Detailed Description

Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

The application provides a shifting fork control method and device of a double-clutch automatic gearbox. According to the driving mode and the shifting type, the moving speed of the shifting fork is automatically adjusted, the speed of combining gears is increased or decreased as required, and the driving experience under different driving modes and different shifting types is improved.

As shown in fig. 2, the shift fork of the DCT is controlled in combination by two switching valves GASV1 and GASV2, two flow control proportional valves SCV1 and SCV2, and two pressure control proportional valves GPCV1 and GPCV 2. The switching valve controls the flowing direction of the oil liquid, and further controls the pushing direction of the shifting fork. The flow control proportional valve SCV controls the flow of the hydraulic piston, the SCV1 valve controls 1/3/5 gear, and the SCV2 valve controls 2/4/6/R gear. The pressure control proportional valve GPCV controls the pressure of the hydraulic piston, the GPCV1 valve controls 1/3/5 gear, and the GPCV2 valve controls 2/4/6/R gear.

Thus, the engaged coupling speed is controlled by both the SCV and GPCV valves. The greater the SCV flow and the greater the GPCV pressure, the faster the gears will engage, and the more likely it will be to produce gear noise and vibration.

As shown in fig. 3, the shift fork control method of the dual clutch automatic transmission provided by the present application includes:

s310: in response to a shift request, a current driving mode and a current shift type are obtained.

As one example, the driving modes include an economy mode ECO, a standard mode D, and a power mode S. Other personalized driving patterns may also be included.

As an example, the shift types include a dynamic upshift PONU, a non-dynamic upshift (i.e., a coast upshift) POFU, a dynamic downshift 1-gear POND, a dynamic downshift 2-gear POND2, a dynamic downshift 3-gear POND3, and a non-dynamic downshift (i.e., a coast downshift) POFD.

S320: and determining a first correction coefficient of a pressure control proportional valve GPCV and a second correction coefficient of a flow control proportional valve SCV corresponding to the target gear in the gear shifting request according to the current driving mode and the current gear shifting type.

Specifically, for each combination of driving mode and shift type, there is one first correction coefficient and one second correction system.

As an embodiment, the correspondence relationship may be recorded by a two-dimensional table, and the correction coefficient may be determined by looking up the two-dimensional table. Please see table 1:

TABLE 1 Driving mode, shift type and correction factor correspondence Table

X1

X2

X3

X4

X5

X6

Y1

Z11

Z12

Z13

Z14

Z15

Z16

Y2

Z21

Z22

Z23

Z24

Z25

Z26

Y3

Z31

Z32

Z33

Z34

Z35

Z36

Wherein, Y1, Y2 and Y3 represent driving modes, and X1, X2, X3, X4, X5 and X6 represent gear shifting types. Z11.

Taking the above-described embodiments of the driving pattern and the shift pattern as examples, table 2 shows an example of the first correction coefficient, and table 3 shows an example of the second correction coefficient.

TABLE 2 first correction factor Table

	PONU	POFU	POND	POND2	POND3	POFD
							ECO
	1	1	1	1	1	1
							D	1	1	1.5	1.5	1.5	1
S	1.5	1.5	2	2	2	1.5

TABLE 3 second correction coefficient Table

It is understood that tables 2 and 3 are one example thereof, and the first correction coefficient and the second correction coefficient mainly depend on the expected values of the shift shock and the shift time corresponding to the vehicle type. Therefore, the first correction coefficient and the second correction coefficient are different for different vehicle types.

Overall, the ECO mode is dominated by comfort, and can properly increase the gear engaging time, reduce the gear engaging force, reduce gear engaging noise and vibration, and maintain good drivability. The S mode takes power response as a main part, can promote the moving speed of a shifting fork, reduce the gear engaging time and promote the gear engaging force, and the driving performance can be reduced to a certain extent. The D mode is between the S mode and the ECO mode. Thus, as an example, the first correction factor and the second correction factor for each shift type in the standard driving mode are respectively equal to or greater than the first correction factor and the second correction factor for the same shift type in the eco driving mode, and the first correction factor and the second correction factor for each shift type in the power driving mode are respectively equal to or greater than the first correction factor and the second correction factor for the same shift type in the standard driving mode.

As an embodiment, under the working conditions of sliding upshifting, sliding downshifting and the like, noise and vibration of a vehicle in an unpowered state are small, gear combination speed can be properly reduced, noise and abnormal sound are reduced more, and comfort is improved. Under the working conditions of dynamic downshift and dynamic upshift, the comfort can be properly sacrificed to improve the response, and the gear engaging time is shortened. Therefore, as an example, in the same driving mode, the first correction factor and the second correction factor for the power downshift are respectively equal to or greater than the first correction factor and the second correction factor for the power upshift. In the same driving mode, the first correction coefficient and the second correction coefficient of the dynamic upshift are respectively larger than or equal to the first correction coefficient and the second correction coefficient of the coasting upshift and the coasting downshift.

It is to be understood that the correction coefficients corresponding to the driving mode and the shift type may be recorded in other forms, and the relationship between the correction coefficients of different driving modes and different shift types may be set as needed.

S330: and correcting the initial pressure of the pressure control proportional valve GPCV during gear combination according to a first correction coefficient to obtain corrected initial pressure, and correcting the initial flow of the flow control proportional valve SCV during gear combination according to a second correction coefficient to obtain corrected initial flow.

As an example, the initial pressure of the pressure control proportional valve GPCV when engaging the gear is determined according to the current oil temperature of the gearbox and the target gear. As one example, as shown in FIG. 4, the GPCV initial pressure at gear-engaging may be determined by querying the GPCV initial pressure gauge at gear-engaging.

As an example, the initial pressure of the GPCV at the gear combination multiplied by a first correction factor is used as the corrected initial pressure, see FIG. 4.

As an embodiment, the initial flow of the proportional valve SCV is controlled according to the current state of the transmission, the target gear and the real-time position of the shifting fork corresponding to the target gear when the gears are combined. The current state of the gearbox comprises the current vehicle speed, the current position of a gear shifting lever, a gear shifting instruction and the like. As one example, the initial flow of the SCV during gear engagement is determined by querying an initial flow meter of the flow control proportional valve SCV during gear engagement, as shown in FIG. 5.

As an embodiment, the product of the SCV initial flow and the second correction coefficient when the gears are combined is used as the corrected initial flow, see fig. 5.

S340: the current target pressure of the pressure control proportional valve GPCV and the current target flow of the flow control proportional valve SCV are calculated.

As one example, as shown in fig. 4, calculating the current target pressure of the pressure control proportional valve GPCV includes:

p1: and acquiring the current state of the gearbox and the real-time position of the shifting fork corresponding to the target gear in the gear shifting request.

P2: and determining the pressure change gradient of the pressure control proportional valve GPCV when the gears are combined according to the current state of the gearbox, the target gear and the real-time position of the shifting fork. As one example, as shown in FIG. 4, the gradient of GPCV pressure change at gear-engaging is determined by querying a gradient table of GPCV pressure change at gear-engaging.

P3: and inputting the corrected initial pressure and the pressure change gradient into an integral calculator to obtain output data of the integral calculator.

P4: and determining the maximum pressure limit value of the pressure control proportional valve GPCV when the gears are combined according to the current oil temperature of the gearbox. As an example, as shown in fig. 4, the maximum pressure limit of the pressure control proportional valve GPCV at the gear engagement is determined by looking up a maximum pressure limit table of the pressure control proportional valve GPCV at the gear engagement.

P5: the lesser of the maximum pressure limit and the output data of the integral calculator is taken as the current target pressure of the GPCV.

As an embodiment, as shown in fig. 5, calculating the current target flow of the flow control proportional valve SCV includes:

q1: and determining the maximum flow limit value of the SCV when the gears are combined according to the current oil temperature of the gearbox. As an example, as shown in fig. 5, the maximum flow limit value of the flow control proportional valve SCV at the time of shift combination is determined by referring to a maximum flow limit table of the flow control proportional valve SCV at the time of shift combination.

Q2: and taking the smaller of the maximum flow limit value and the corrected initial flow as the current target flow.

S350: and controlling the shifting fork corresponding to the target gear in the gear shifting request to move according to the current target pressure and the current target flow, so as to realize the gear engaging operation of the target gear.

Specifically, after receiving a gear shift request, the transmission control system TCU controls the pressure control proportional valve GPCV and the flow control proportional valve SCV in real time according to the current target pressure and the current target flow to control the movement of the hydraulic piston, and resets the shift force to zero by a reset activation command when detecting that the shift fork position is in the shift state.

Based on the shifting fork control method, the application also provides a shifting fork control device of the double-clutch automatic gearbox. As shown in fig. 6, the fork control apparatus includes an information obtaining module 610, a correction coefficient determining module 620, a correcting module 630, a current pressure and flow calculating module 640, and a control module 650.

The information acquisition module 610 is configured to acquire a current driving mode and a current shift type in response to a shift request.

The correction factor determining module 620 is used for determining a first correction factor of the pressure control proportional valve and a second correction factor of the flow control proportional valve corresponding to the target gear in the gear shifting request according to the current driving mode and the current gear shifting type.

The correcting module 630 is configured to correct the initial pressure of the pressure control proportional valve during gear combination according to a first correction coefficient to obtain a corrected initial pressure, and correct the initial flow of the flow control proportional valve during gear combination according to a second correction coefficient to obtain a corrected initial flow.

The current pressure and flow calculation module 640 is used to calculate the current target pressure of the pressure control proportional valve and the current target flow of the flow control proportional valve.

The control module 650 is configured to control shifting fork movement corresponding to a target gear in the shift request according to the current target pressure and the current target pressure, so as to implement a shift operation of the target gear.

On the basis of not changing the hardware structure of the gearbox, the gear combination and separation control strategy is optimized, and the driving quality is effectively improved.

Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.

Claims

1. A shift fork control method of a double-clutch automatic gearbox is characterized by comprising the following steps:

determining a first correction coefficient of a pressure control proportional valve and a second correction coefficient of a flow control proportional valve corresponding to a target gear in the gear shifting request according to a current driving mode and a current gear shifting type;

correcting the initial pressure of the pressure control proportional valve during gear combination according to the first correction coefficient to obtain corrected initial pressure, and correcting the initial flow of the flow control proportional valve during gear combination according to the second correction coefficient to obtain corrected initial flow;

controlling a shifting fork corresponding to a target gear in the gear shifting request to move according to the current target pressure and the current target flow, and realizing the gear engaging operation of the target gear;

the first correction coefficient and the second correction coefficient of each gear shifting type in the standard driving mode are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type in the economical driving mode;

the first correction coefficient and the second correction coefficient of each gear shifting type in the power driving mode are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type in the standard driving mode;

under the same driving mode, the first correction coefficient and the second correction coefficient of the dynamic downshift are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the dynamic upshift;

2. The shift fork control method of a dual clutch automatic transmission according to claim 1, wherein calculating the current target pressure of the pressure control proportional valve includes:

determining the pressure change gradient of the pressure control proportional valve when gears are combined according to the current state of the gearbox, the target gear and the real-time position of the shifting fork;

inputting the corrected initial pressure and the pressure change gradient into an integral calculator to obtain output data of the integral calculator;

3. The shift fork control method of a dual clutch automatic transmission according to claim 1 or 2, wherein the initial pressure of the pressure control proportional valve is controlled according to the current oil temperature of the transmission and the target gear determination gear combination.

4. The shift fork control method of a dual clutch automatic transmission according to claim 1, wherein an initial flow rate of the flow control proportional valve at the time of gear combination is determined according to a current state of the transmission, the target gear, and a real-time position of the shift fork corresponding to the target gear.

5. The shift fork control method of a dual clutch automatic transmission according to claim 1 or 4, wherein calculating the current target flow rate of the flow rate control proportional valve includes:

determining the maximum flow limit value of the flow control proportional valve when the gears are combined according to the current oil temperature of the gearbox;

6. The shifting fork control device of the double-clutch automatic gearbox is characterized by comprising an information acquisition module, a correction coefficient determination module, a correction module, a current pressure and flow calculation module and a control module;

the information acquisition module is used for responding to a gear shifting request and acquiring a current driving mode and a current gear shifting type;

the correction coefficient determining module is used for determining a first correction coefficient of a pressure control proportional valve and a second correction coefficient of a flow control proportional valve corresponding to a target gear in the gear shifting request according to a current driving mode and a current gear shifting type;

the correction module is used for correcting the initial pressure of the pressure control proportional valve during gear combination according to the first correction coefficient to obtain corrected initial pressure, and correcting the initial flow of the flow control proportional valve during gear combination according to the second correction coefficient to obtain corrected initial flow;

the control module is used for controlling a shifting fork corresponding to a target gear in the gear shifting request to move according to the current target pressure and the current target flow, so that the gear shifting operation of the target gear is realized;

under the standard driving mode, the first correction coefficient and the second correction coefficient of each gear shifting type are respectively greater than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type under the economic driving mode;

under the power driving mode, the first correction coefficient and the second correction coefficient of each gear shifting type are respectively larger than or equal to the first correction coefficient and the second correction coefficient of the same gear shifting type under the standard driving mode;

under the same driving mode, a first correction coefficient and a second correction coefficient of the dynamic downshift are respectively greater than or equal to a first correction coefficient and a second correction coefficient of the dynamic upshift;