JP2873614B2 - Device for learning characteristics of fluid transmission in transmission with fluid transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention learns characteristic values of a fluid transmission device in a transmission with a fluid transmission device such as an automatic transmission for an automobile, for the purpose of improving shift control accuracy and the like. Related to the device.

<Prior art> In an automatic transmission or a continuously variable transmission for an automobile, the output of an engine is input to a gear type transmission via a fluid transmission device such as a torque converter or a fluid coupling, and a clutch is used in the gear type transmission. The gears are shifted by coupling and releasing gear shifting elements such as band brakes.

Here, the operating oil pressure for performing the shift operation is generally set based on the throttle valve opening of the engine and the vehicle speed, but is originally a value corresponding to the input torque to the transmission. However, this is preferable for tuning when increasing transmission efficiency or reducing shift shock.

For this reason, as disclosed in Japanese Utility Model Laid-Open Publication No. 1-69947, a fluid transmission device (torque converter) which detects the input rotation speed and the output rotation speed of the transmission and further obtains the speed ratio corresponding to these speed ratios. The input torque is estimated on the basis of the characteristic value and the operating oil pressure is controlled based on the input torque.

<Problems to be Solved by the Invention> However, since the characteristics of the fluid transmission device vary from product to product and change over time, it is difficult to accurately estimate the input torque. Was impaired.

It is also conceivable to provide a torque sensor on the output shaft of the transmission to detect the output torque and estimate the input torque based on the output torque and the gear ratio of the gear type transmission. Estimation was impossible due to too large response delay.

The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a characteristic learning device of a fluid transmission device in a transmission with a fluid transmission device capable of accurately estimating an input torque. I do.

<Means for Solving the Problems> For this reason, as shown in FIG. 1, the present invention relates to a transmission with a fluid transmission configured by connecting an input-side fluid transmission and an output-side gear transmission. A transmission output torque detecting means for detecting an output torque of the gear transmission, a gear ratio detecting means for detecting a gear ratio of the gear transmission, and a transmission input rotation for detecting an input rotation speed of the fluid transmission. Number detection means, transmission output rotation number detection means for detecting the output rotation number of the fluid transmission device, and characteristics for rewritably storing the characteristic value of the fluid transmission device with respect to the speed ratio between the input rotation number and the output rotation number. Value storage means for calculating a characteristic value of the fluid transmission based on the output torque of the transmission, the gear ratio, and the input speed of the fluid transmission, and calculating the characteristic of the corresponding speed ratio stored in the characteristic value storage means. Modify and rewrite value Characteristic value learning means.

Further, the characteristic value learning means may be configured to rewrite the characteristic value only when the gear type transmission is in a non-shift state and the input rotational speed and the output rotational speed are in a substantially steady state.

<Operation> The characteristic value learning means includes an output torque of the gear transmission detected by the transmission output torque detection means, a gear ratio of the gear transmission detected by the gear ratio detection means, and a transmission input rotation speed. A characteristic value of the fluid transmission is calculated based on the input rotation speed of the fluid transmission detected by the detection means, and a characteristic value corresponding to the speed ratio stored in the characteristic value storage means based on the calculated characteristic value. Is modified and rewritten.

As a result, it is possible to accurately detect the characteristic value that varies with fluctuations and aging due to the transmission by learning, and to use this value to estimate the input torque during gear shifting with high accuracy, and to set the operating oil pressure and the like. Can be used for
When a failure occurs in the output torque detecting means and the like, the steady-state input torque can be estimated using the characteristic values learned up to that time.

Further, as described above, since the input torque cannot be accurately detected from the output torque of the transmission during the gear shift (for this reason, the input torque is estimated from the characteristic value), the input rotation is not performed when the gear is not shifted. If the characteristic value is learned only when the number and the output rotational speed are in a substantially steady state, the learning accuracy can be improved.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

Referring to FIG. 2, an automatic transmission 2
Is provided. The automatic transmission 2 includes a pump impeller 3a and a turbine impeller 3b interposed on the output side of the engine 1.
And a solenoid valve 5 for controlling the operating oil pressure for hydraulic actuators such as a forward clutch and a band brake in the gear type transmission 4. Reference numeral 6 denotes an output shaft of the automatic transmission 2.

The duty of the electromagnetic valve 5 is controlled by a control unit 7 with a built-in microcomputer to control the shifting hydraulic pressure.

The control unit 7 receives signals from various sensors.

As the various sensors, a potentiometer type throttle sensor 9 for detecting an opening TVO of a throttle valve 8 of an intake system of the engine 1 is provided.

Further, an engine speed sensor 10 as a transmission device input speed detecting means for detecting the engine speed N _E from the output shaft of the engine 1, that is, the input speed (pump speed) of the torque converter 3 which is a fluid power transmission device. Is provided.

Further, a torque converter output speed sensor 11 is provided as a transmission output speed detecting means for detecting the output speed (turbine speed) _NT of the torque converter 3.

Further, a magnetostrictive torque sensor 12 is provided as transmission output torque detecting means which is attached to the output shaft 6 of the gear type transmission 4 and detects the output torque TRQ. Incidentally, a magnetostrictive torque sensor is well known from Japanese Patent Application Laid-Open No. Sho 64-21255.

In addition, a gear ratio sensor 13 is provided as gear ratio detection means for detecting the gear ratio i of the gear transmission 4.

Here, the control unit 7 learns the characteristic values of the torque converter 3 according to the present invention and sets the operating oil pressure based on the input torque according to the flowchart of FIG.

In step 1 (shown as S1 in the figure, the same applies hereinafter), the engine speed _NE and the turbine speed _NT are read.

 In step 2, it is determined whether or not a shift is being performed.

If not in shift determines the rate of change of the engine rotational speed N _E is whether less than a predetermined value .DELTA.N _E proceeds to step 3.

Step 3 of the determination is YES, that is, if the engine speed is determined to substantially constant rate of change of the turbine speed N _T proceeds to step 4 determines whether less than a predetermined value .DELTA.N _T.

If the determination in step 4 is YES, that is, if it is determined that the turbine rotation is substantially steady, the process proceeds to step 5 where the current output torque T _O and gear ratio i are read.

In step 6, the input torque (turbine torque) T of the transmission is determined based on the output torque T _O and the gear ratio i.
Calculate _T1 (= T _O / i).

In step 7, the engine speed _NE and the turbine speed
Calculating a speed ratio _{e (= N T / N E} ) of the N _T.

In step 8, based on the speed ratio e obtained in step 7, the characteristic value t · τ of the torque converter 3 which is a product of the torque ratio t and the input torque capacity coefficient τ (see FIG. 4 for each characteristic) Is searched from the table map stored in the RAM of the microcomputer (when a map of a basic value and a correction value described later is separately provided, a ROM for storing the basic value and a RAM for storing the correction value). Here, the RAM that freely stores the data of the characteristic values t · τ constitutes characteristic value storage means.

In step 9, estimates calculated by the following equation based on the input torque T _T2 of the transmission to said speed ratio e and the engine speed N _E.

T _T2 = t · τ × N _E ² This input torque estimation method is well known from Japanese Utility Model Laid-Open No. 1-69947.

In step 10, the input torque T _T1 detected in step 6 is compared with the input torque T _T2 estimated in step 9, and when the difference between them is less than or equal to a predetermined value ΔT _T , the torque sensor 12 and the gear proceed ratio sensor 13 is determined to be normal to a step 11, the working oil pressure L _O of the steady state, is set based on the input torque T _T1 detected in step 6.

Then, in step 12, the output torque T _O, based on the gear ratio i and the engine speed N _E, newly obtains the characteristic value t · tau in the operating conditions by the following equation.

t · τ = T _O / (i · N _E ² ) = T _T1 / N _E ^{2 In} step 13, the characteristic value t ·
The data of t · τ corresponding to the speed ratio e obtained in step 7 is corrected and rewritten according to the data of τ.

The functions of steps 12 and 13 constitute characteristic value learning means.

Further, when the difference between the detected input torque T _T1 and the estimated input torque T _T2 exceeds the predetermined value ΔT _T in Step 10, it is determined that the torque sensor 12 or the gear ratio sensor 13 is abnormal, and the process proceeds to Step 14. The constant operating oil pressure L _O is set based on the input torque T _T2 estimated in step 9, and this routine ends without performing the correction and rewriting of t · τ.

Further, at the time of gear shifting in which the determination in step 2 is YES, or during unsteady operation in which one of steps 3 and 4 is NO, the speed ratio e is obtained in step 15 and the characteristic value t · τ is searched in step 16 estimates calculates input torque T _T2 in the same calculation formula and step 9 in step 17, setting the working hydraulic pressure L _S in the gear shifting based on the input torque T _T2 which is the estimated in step 18.

In this way, the transmission input torque can be prevented from being detected by the output torque, and in addition to a shift or an unsteady state, even when the torque sensor or the like becomes abnormal during the steady state, it is possible to avoid the influence of variations in the transmission and changes over time. Learned characteristic value t
It is possible to detect with high accuracy using τ, and it is possible to set the operating oil pressure with high accuracy using the detected input torque.

In this embodiment, an automatic transmission having a torque converter has been described. However, the present invention can be similarly applied to a continuously variable transmission having a fluid coupling.

<Effects of the Invention> As described above, according to the present invention, the configuration is such that the characteristics of the fluid transmission device are learned based on the output torque of the transmission, the gear ratio, and the input rotation speed of the fluid transmission device. The input torque used for setting the working oil pressure can be estimated with high accuracy. It has features that the input torque can be estimated with high accuracy and that a fail-safe function can be achieved.

[Brief description of the drawings]

FIG. 1 is a block diagram of a claim correspondence of the present invention, FIG. 2 is a diagram showing a system configuration of an embodiment of the present invention, and FIG. FIG. 4 (A) is a diagram showing the relationship between the torque ratio and the input torque capacity coefficient with respect to the speed ratio of the torque converter, and FIG. 4 (B) is the diagram showing the relationship between the torque ratio and the input torque capacity coefficient with respect to the speed ratio. FIG. 4 is a diagram illustrating a relationship between characteristic values represented as products. DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Automatic transmission, 3 ... Torque converter, 4 ... Gear type transmission, 7 ... Control unit, 10
... engine speed sensor, 11 ... torque converter output speed sensor, 12 ... torque sensor, 13 ... gear ratio sensor

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16H 59/00-6 / 12,61 / 16-61/24 F16H 63/40-63/48 G01L 3/00

Claims (2)

(57) [Claims] 1. A transmission output torque detection for detecting an output torque of a gear transmission in a transmission with a fluid transmission configured by connecting an input fluid transmission and an output gear transmission. Means, gear ratio detecting means for detecting the gear ratio of the gear transmission, transmission input speed detecting means for detecting the input speed of the fluid transmission, and transmission device for detecting the output speed of the fluid transmission. Output rotation speed detection means, and characteristic value storage means for rewritably storing a characteristic value of the fluid transmission device with respect to a speed ratio between the input rotation speed and the output rotation speed,
A characteristic value of the fluid transmission is calculated based on the output torque of the transmission, the gear ratio, and the input speed of the fluid transmission, and the characteristic value of the corresponding speed ratio stored in the characteristic value storage unit is corrected. And a characteristic value learning means for rewriting the characteristic value learning means. 2. The characteristic value learning means performs rewriting of a characteristic value only when the gear type transmission is in a non-shift state and the input rotational speed and the output rotational speed are in a substantially steady state.
The characteristic learning device of the fluid transmission device in the transmission with the fluid transmission device according to the above.