JP2847381B2 - Line pressure control device for automotive automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a line pressure control device for an automatic transmission (automatic transmission) for a vehicle.

<Conventional technology> In an automatic transmission for an automobile, the line pressure is obtained by regulating the discharge pressure of an oil pump, and the line pressure is supplied to a hydraulic circuit to operate the hydraulic pressure of a torque converter and various transmission elements in a gear type transmission. However, the conventional line pressure control is performed so as to approach a target value based on a predetermined control constant (see Japanese Patent Application Laid-Open No. 62-9054).

That is, in the automatic transmission, the line pressure, which is the source of the operating oil pressure of the torque converter and various speed change elements, needs to be adjusted to an appropriate oil pressure according to the engine output. As a result, the vibration of the engine and the shift shock are transmitted to the axle, so that noise and vibration increase. On the other hand, if the hydraulic pressure is lower than the appropriate oil pressure, slippage occurs, the transmission efficiency decreases, the durability of the automatic transmission deteriorates, and the fuel efficiency deteriorates.

Therefore, conventionally, a map in which a control value of the line pressure is determined in advance corresponding to the throttle valve opening and the like is provided, and the line pressure is controlled based on the map.

For this reason, the control characteristic target of the line pressure has been predetermined.

<Problems to be Solved by the Invention> However, if the control characteristic target of the line pressure is set in advance as described above, for example, the following conflicting requirements cannot be satisfied. However, there is a problem that it is not optimal in a specific driving state, and it is difficult to respond to various user preferences and needs evenly.

At the time of traffic congestion, it is required to reduce the line pressure to increase the slip ratio to some extent to reduce the shock, etc. in order to make the riding comfort oriented.

During sports running, it is desired to increase the line pressure to reduce the slip ratio and improve response and the like.

In view of such conventional problems, the present invention analyzes the factors based on operating state parameters such as throttle valve disclosure, engine speed, and the like, and analyzes operating conditions (e.g., traffic congestion traveling, city area traveling, high speed traveling, sports traveling, etc.). It is another object of the present invention to provide a line pressure control device for an automatic transmission for a vehicle, which can recognize and determine the driving environment) and optimize the line pressure control based on the recognition and judgment.

<Means for Solving the Problems> For this reason, as shown in FIG. 1, the present invention relates to an automobile for detecting and measuring a state quantity of a predetermined line pressure control parameter, and setting and controlling the line pressure based on the detected state quantity. In the line pressure control device of the automatic transmission, the following means (A) to (E) are provided.

(A) Operating state parameter detecting means for obtaining time series data by sampling state quantities of a plurality of operating state parameters including at least a throttle valve opening and an engine speed for each unit time. (B) For each operating state parameter Means for generating representative data having a high frequency based on the frequency distribution from the time-series data; and (C) a plurality of driving operations using an evaluation function based on driving state parameters for a plurality of driving states including at least predetermined traffic congestion. Satisfaction calculating means for calculating satisfaction of each evaluation function based on representative data of state parameters (D) Operating state determining means for determining an operating state from each satisfaction of a plurality of evaluation functions (E) Operating state determination A line pressure correcting means for correcting the line pressure according to the result and reducing the line pressure at least during traffic congestion Action> (A) above the operating state recognition device having the means ~ (D) is basically performs a fuzzy inference, for example, the second
As shown in the figure, the driving states to be recognized and determined are classified into, for example, traffic congestion driving, city driving, high-speed driving, and sports driving. The throttle valve opening TVO, the rate of change ΔTVO / Δt, and the engine speed N in these driving states , The approximate state quantity (small / medium / large) of operating state parameters such as the rate of change ΔN / Δt
Is determined in advance, and this is used as an evaluation function (membership function) of the operating state.

When recognizing the operating state, first open the throttle valve
Time-series data is obtained by sampling state quantities of a plurality of operating state parameters such as VTO and engine speed N for each unit time.

Next, representative data is created from the time-series data for each operating state parameter.

For example, for each operating state parameter, each sampling data is evaluated according to an evaluation function based on a state quantity for a predetermined small to large section and assigned to the corresponding small to large section, and the sampling data assigned to each section is evaluated. The representative data is created based on the frequency distribution of.

Next, the satisfaction level of each evaluation function is calculated based on the representative data of the plurality of operating state parameters using the predetermined plurality of operating state evaluation functions.

For example, for each operating state parameter, the representative data is evaluated according to an evaluation function based on the operating state parameters for a plurality of predetermined operating states and assigned to the corresponding operating state, and the distribution of the representative data assigned to each operating state is determined. Calculate satisfaction.

Next, the operating state is determined from the degree of satisfaction of each of the plurality of evaluation functions, directly, or by obtaining a weighted average or the like and quantifying the operating state to determine the operating state.

The line pressure control of the automatic transmission is optimized by the means (E) using the operation state determination result of the operation state recognition device.

That is, when a state quantity of a predetermined line pressure control parameter (for example, a throttle valve opening) is detected, and the line pressure is set and controlled based on the detected state quantity, according to the operation state determination result, that is, congestion traveling, city area traveling, high-speed traveling. , The line pressure is corrected to an optimum one according to sports driving or the like.

<Examples> Examples of the present invention will be described below.

 First, the driving state recognition device will be described.

The driving state recognition device is constituted by a control unit with a built-in microcomputer, and is connected to a well-known throttle sensor, excessive crank sensor, vehicle speed sensor, gear position sensor, and the like.

Then, based on signals from these sensors, as a driving state parameter for driving state recognition, the throttle valve opening TVO, its change ΔTVO / Δt, the engine speed N, its change rate ΔN / Δt, the vehicle speed VSP, its Change rate ΔVSP / Δt, gear position (L,
M, H) and the gear position change frequency (the number of shifts / time) are detected for each unit time.

However, in the following, for convenience of explanation, the operation state parameters will be limited to the throttle valve opening TVO and the engine speed N.

The recognition of the operating state by the control unit is performed according to the flowchart of FIG.

In step 1 (indicated as S1 in the figure, the same applies hereinafter), the throttle valve opening VTO is sampled every unit time to obtain time-series data of the throttle valve opening TVO in a predetermined time section.

Step 1 corresponds to the operating state parameter detecting means.

In step 2, the evaluation is performed for each of the sampling data using a predetermined small, medium, and large evaluation function for the throttle valve opening VTO, and assigned to small, medium, and large.

For example, if the sampling data of the throttle valve opening at a certain point in time t ₁ is TVO _1, small 0.7, in 0.3, allocates as large 0.0.

In step 3, small, medium, and large assigned values for all sampling data are integrated to create a small, medium, and large frequency distribution.

In step 4, representative data of the throttle valve opening is determined from the small, medium, and large frequency distribution.

That is, so that the numerical value becomes large in the order of small, medium, large,
The weights w ₁ , w ₂ , and w ₃ are determined in advance (for example, small w ₁ = 0.25, medium w ₂ = 0.50, large w ₃ = 0.75), and each frequency (integrated value of the assigned value) is determined. Assuming a, b, and c, the representative data W is calculated by taking the weighted average from the following equation.

Alternatively, the centroid of the area surrounded by the envelope of the frequency distribution may be obtained, and this may be used as the representative data.

Here, the steps 2 to 4 correspond to representative data creation means.

In step 5, representative data (small / medium / large data)
Then, the representative data is evaluated using a predetermined evaluation relation of the driving state, and assigned to traffic congestion, city area driving, high-speed driving, and sports driving.

For example, when the representative data of the throttle valve opening is W _1, traffic jam running 0.3, urban 0.7, high speed 0.0, sports cars
Assign as 0.0.

In steps 1 'to 5', the same processing is performed on the engine speed N in parallel with steps 1 to 5 to evaluate the representative data of the engine speed N. Assign to running and sports running.

 Next, proceed to steps 6 and 7.

In step 6, the assigned values of traffic congestion traveling, city area traveling, high-speed traveling, and sports traveling for all the driving state parameters are integrated, and their frequency distributions are created.

This frequency distribution is represented by the total value of each frequency (a + b + c + d)
Is compressed to be 1 to indicate satisfaction.

Here, steps 5 and 6 correspond to the satisfaction degree calculating means.

In step 7, traffic congestion, city driving, high-speed driving,
A determination value of the driving state is obtained from each degree of satisfaction with the sport running.

That is, the weights x ₁ , x ₂ , x ₃ , and x ₄ of each of these driving states are determined in advance so that the numerical values become larger in the order of traffic congestion, city driving, high-speed driving, and sports driving (for example, , Traffic congestion x ₁ = 0.2, city driving x ₂ = 0.4, high speed driving x ₃ =
0.6, sports running x ₄ = 0.8), and assuming that each frequency value is a, b, c, d, a weighted average is calculated from the following formula to calculate the determination value X.

Alternatively, the centroid of the area enclosed by the envelope of the distribution of satisfaction may be obtained, and this may be used as the determination value.

Here, the step 7 corresponds to the operating state determination means.

As described above, the determination value X of the driving state is obtained, and the small to large values thereof represent traffic congestion traveling, city area traveling, high speed traveling, and sports traveling.

Therefore, by supplementing the line pressure of the automatic transmission in accordance with the determination value X, line pressure control suitable for the operation state can be performed.

Next, a line pressure control device for an automatic transmission will be described.

Referring to FIG. 4, an automatic transmission 2 is provided on the output side of the engine 1.
Is provided. The automatic transmission 2 includes a torque converter 3 connected to an output shaft of the engine 1, a gear transmission 4 connected to the output shaft of the torque converter 3, and various transmission elements in the gear transmission 4. A hydraulic actuator 5 for performing a coupling / release operation. The operating oil pressure for the hydraulic actuator 5 is turned ON / OF by operating various electromagnetic valves.
Although F control is performed, only the shift electromagnetic valves 6A and 6B for automatic shifting are shown here.

Here, an oil pump 7 driven by an input shaft of a gear type transmission is used, and an orifice 8, an electromagnetic valve 9, a pressure modification A valve 10 and a pressure regulator valve 11 are provided.

The duty of the solenoid valve 9 is controlled as described below, and the solenoid valve 9 obtains a pilot pressure based on the discharge pressure of the oil pump 7 guided through the orifice 8. The pressure modifier valve 10 amplifies the pilot pressure. The pressure regulator valve 11 regulates the discharge pressure from the oil pump 7 to a line pressure proportional to the pilot pressure from the pressure modifier valve 10 and sends the line pressure to hydraulic circuits such as the torque converter 3 and the hydraulic actuator 5.

The control unit 12 has a built-in microcomputer and controls the lamp pressure by performing duty control of the electromagnetic valve 9 based on signals from various sensors. Specifically, the line pressure can be increased by increasing the duty DUTY. The control unit 12 includes the shift electromagnetic valve.
By controlling 6A, 6B, etc., the hydraulic actuator 5
The transmission of the gear-type transmission 4 is controlled via the transmission, but the description of such transmission control will be omitted below.

The various sensors include a throttle sensor 14 that detects an opening TVO of a throttle valve 13 of an intake system of the engine 1.
Is provided.

A crank angle sensor 15 is provided on the output shaft of the engine 1 or a shaft that rotates in synchronization with the output shaft. The signal from the crank angle sensor 15 is, for example, a pulse signal for each reference crank angle, and the engine speed N is calculated from its cycle.

Further, a vehicle speed sensor 16 that obtains a rotation signal from an output shaft of the gear transmission 4 and detects a vehicle speed VSP is provided.

Next, the line pressure control by the control unit 12 will be described with reference to the flowchart of FIG.

In step 11, the throttle valve opening TVO and the vehicle speed VSP as the line pressure control parameters are read.

In step 12, reference is made to a map in which the duty DUTY to the electromagnetic valve 9 for obtaining the optimum line pressure in accordance with the throttle valve opening TVO and the vehicle speed VSP is determined in advance, and the actual TVO, VS
Set the duty DUTY from P by searching. Here, the duty DUTY is determined mainly in proportion to the throttle valve opening TVO, and the vehicle speed VSP is an auxiliary determining factor.

In step 13, the correction coefficient C is searched for from the determination value X with reference to a map in which the correction coefficient C is determined in advance according to the above-described determination value X of the operating state. Here, the correction coefficient C is the determination value X
Is set to take a small value when is a small value corresponding to traffic congestion.

In step 14, the duty set in step 12
DUTY is corrected by the correction coefficient C as in the following equation.

DUTY ← DUTY · C That is, the duty DUTY is decreased so as to decrease the line pressure during traffic congestion, and the duty DUTY is increased so as to increase the line pressure during sports traveling.

Here, the steps 13 and 14 correspond to the line pressure correcting means.

In step 15, a control signal having the duty DUTY is output to drive the electromagnetic valve 9, thereby obtaining a line pressure corresponding to the duty DUTY.

As a result, when the vehicle is traveling in a congested state where the driving state determination value X is small, the line pressure is reduced, the slip ratio is increased, the shock is reduced, and the riding comfort is improved. There is no problem with the durability of the automatic transmission, and there is no significant effect on fuel economy.

In addition, during sports running in which the determination value X of the driving state is large, the line pressure is increased and the slip ratio is reduced. As a result, the shift is improved, but the response is improved.

At the time of such sports running, it is preferable that the shift pattern is also corrected and all the shift points are moved to the high vehicle speed side so as to be pulled.

If, for example, it is determined whether or not the vehicle is traveling in congested traffic, instead of performing correction using the determination value X of the final driving state, reference is made to step 6 in FIG. 3 and a / (a + b + c).
Since + d) indicates the degree of congestion traveling satisfaction, this may be compared with a predetermined value to determine whether or not congestion traveling, and correction may be made based on the result.

<Effect of the Invention> As described above, according to the present invention, based on operating state parameters such as a throttle valve opening and an engine speed,
By analyzing factors, it is possible to recognize and determine driving conditions (or driving environment) such as traffic congestion driving, city driving, high-speed driving, sports driving, etc., and to optimize line pressure control of the automatic transmission based on this. A line pressure suitable for various operating conditions can be realized, and an effect of greatly improving the driving feeling can be obtained.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of the present invention, FIG. 2 is a diagram showing an evaluation function of an operating state, FIG. 3 is a flowchart of operating state recognition showing an embodiment of the present invention, and FIG. FIG. 5 is a system diagram of a line pressure control device for a transmission, and FIG. 5 is a flowchart of line pressure control. DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Automatic transmission, 3 ... Torque converter, 4 ... Gear type transmission, 7 ... Oil pump, 9
…… Electromagnetic valve, 10 …… Pressure regulator modifier valve, 11 …… Pressure regulator valve,
12 ... Control unit, 14 ... Throttle sensor, 15 ... Crank angle sensor, 16 ... Vehicle speed sensor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (1)

(57) [Claims] 1. A line pressure control device for an automatic speed machine for an automobile, which detects a state quantity of a predetermined line pressure control parameter and sets and controls a line pressure based on the detected amount. Operating state parameter detecting means for sampling the state quantities of a plurality of operating state parameters including unit time for each unit time to obtain time-series data; and for each operating state parameter, a representative of a large frequency based on a frequency distribution from the time-series data. Using a representative data creating means for creating data, and an evaluation function based on operating state parameters for a plurality of operating states including at least traffic congestion, based on representative data of the plurality of operating state parameters. A degree-of-satisfaction calculating means for calculating a degree of operation; Line pressure correction means for correcting the line pressure in accordance with the operation state determination result and reducing the line pressure at least during traffic congestion. Control device.