KR100226945B1 - Torque estimation method and correction method of torque enumeration data and torque estimation apparatus - Google Patents

Abstract

The present invention enables the transmission torque to be estimated with high accuracy without using an expensive torque sensor, and intentionally slips while lowering the clutch hydraulic pressure (P) of the automatic oscillation clutch 12, and a rotational speed detecting means. The presence or absence of slip is judged on the basis of the detected values of (40, 42), and the engagement torque Tslip of the automatic starting clutch 12 is obtained from the clutch hydraulic pressure P at the start of slip, and this engagement torque Tslip is obtained when the clutch before slip is engaged. It is estimated by the transmission torque of.

Description

Torque estimation method, torque calculation data correction method and torque estimation device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque estimation method, a torque calculation data correction method, and a torque estimation device, and more particularly, to a technique for estimating transmission torque with high accuracy without using an expensive torque sensor.

(Conventional technology)

Recently, as a method of alleviating shift shock of an automatic transmission, a method of performing torque down of engine output by controlling the ignition delay angle of the engine at the time of shift is known. Moreover, in TRC (traction control system), the method of controlling the output of engine torque is known by controlling the fuel injection amount of an engine. In order to control the engine output, it is necessary to actually detect the tire drive torque with high accuracy. However, the conventional torque sensor has a problem in terms of cost and reliability, and it has not been put to practical use in mass production vehicles yet. Therefore, the mainstream method is to estimate the actual torque of the tire from the basic torque map of the engine, the interpolation amount by acceleration and inertia, the torque ratio of the torque converter, and the gear ratio. In addition, according to the Society of Automotive Engineers (950E) 950900, a method of improving the estimation accuracy by using the capacity factor of the torque converter, not just the torque ratio, is introduced.

However, the map for calculating the engine torque from the intake air amount or the throttle valve opening and the engine speed, the torque ratio of the torque converter, the capacity factor, etc. are all set in advance, and variations due to individual differences or disturbances due to irregular changes in manufacturing Does not take into account. In addition, the inertia correction amount obtained by the product of the preset inertia amount and the derivative value of the engine speed (usually, a filter for removing noise) is also large, and irregular variation is large due to the filter, measurement accuracy, and the like. Although a method for correcting such irregular changes by various fluctuation estimation or learning correction has been proposed, it is not possible to obtain a sufficiently satisfactory accuracy.

For this reason, for example, the target engine torque cannot be set with high accuracy in the case of torque down control of the engine for alleviating shift shock or engine torque control by TRC during tire slip, Mitigation and TRC could not be performed with high accuracy.

The present invention has been made on the background of the above problem, and its object is to enable estimation of the transfer torque with high accuracy without using an expensive torque sensor.

(Means to solve the task)

In order to achieve the above object, the first invention provides a torque estimating method for estimating a transmission torque during coupling of a power transmission system in a power transmission system in which a coupling force controllable coupling device is arranged. The coupling force of the coupling device is reduced by intentionally slipping to obtain the coupling torque of the coupling device near the boundary between the slip state and the coupling state, and the transmission torque during the coupling is estimated based on the coupling torque. Torque estimation method.

A second invention is a torque estimating method for estimating transmission torque during engagement when a clutch is connected, in a power transmission system provided with a clutch for connecting and disconnecting power transmission, wherein (a) at the time of engagement of the clutch; A coupling force lowering step of lowering the coupling force of the clutch; (b) a slip determination step of judging whether or not the clutch has started to slip in response to the decrease in the coupling force; and (c) the clutch in the vicinity of the start of slipping of the clutch; The torque is calculated based on the coupling force, and the torque is estimated to be the transmission torque during the coupling.

According to a third aspect of the present invention, in the first or second invention, a slip state is immediately terminated after the estimation of the transmission torque during the engagement is completed to engage the coupling device or the clutch.

A fourth invention relates to a method of correcting torque calculation data, which has a predetermined physical quantity as a parameter, in order to obtain a torque of a predetermined part related to a power transmission system provided with a clutch for connecting and disconnecting power transmission. Therefore, the torque calculation data is corrected by using the estimated transmission torque during the coupling.

A fifth aspect of the present invention provides a torque estimating apparatus for estimating transmission torque during engagement when a clutch is connected in a power transmission system provided with a clutch for connecting and disconnecting power transmission, wherein (a) controlling the engagement force of the clutch. Coupling force control means, (b) a pair of rotational speed detection means for detecting the front and rear rotational speeds of the clutch in the power transmission system, and (c) the engagement force of the clutch by the coupling force control means when the clutch is engaged. (D) slip determination means for judging on the basis of the detected values of the pair of rotational speed detecting means whether or not the clutch starts to slide in accordance with the drop in the engagement force; The engagement torque of the clutch in the vicinity of the sliding of the clutch is calculated based on the engagement force, and the engagement torque is It has a torque estimating means for torque in the moon.

1 is a schematic configuration diagram showing a power transmission device for an automatic vehicle provided with a torque estimating apparatus in which the torque estimating method of the present invention is preferably implemented.

FIG. 2 is a flowchart for explaining the operation in the case where torque down control is executed by using the automatic starting clutch in the embodiment of FIG.

3 is a cross-sectional view of the automatic starting clutch in the embodiment of FIG.

4 is a time chart showing changes in each part when the torque down control is executed in accordance with the flowchart of FIG.

5 is an explanatory diagram showing an example of the relationship between the slip rotational speed ΔN and the friction coefficient μ of the wet clutch and the dry clutch.

FIG. 6 is an explanatory diagram showing still another example of the automatic starting clutch used in the automatic vehicle of FIG.

7 is a flow chart illustrating another embodiment of the present invention.

8 is a flow chart illustrating one embodiment of the invention as claimed in claim 4.

<Description of the symbols for the main parts of the drawings>

12, 50: automatic start clutch (coupling device, clutch) 30: controller

34: pressure regulating valve (coupling force control means) 40, 42: rotational speed detection means

60: actuator (bonding force control means)

Step S1, R1: bonding force lowering step, bonding force lowering command means

Step S1, S3, R3, R4: slip determination step, slip determination means

Steps S4, S5, R2 and R5: Torque Estimating Step, Torque Estimating Means

Here, the present invention is preferably applied to the case of estimating the transmission torque when the power transmission system is coupled using the coupling device provided in the vehicle power transmission system or correcting the torque map of the engine based on the transmission torque during the coupling. In the case of a power transmission system having a coupling device such as a clutch, the transmission transmission system can be applied to the estimation of the transmission torque during engagement in other types of power transmission systems other than the vehicle. In the case of a power transmission system of a vehicle, as a coupling device used for estimating transmission torque during engagement, an oscillation clutch that connects and blocks power transmission between the transmission and the transmission is preferably used. It is also possible to use a shift clutch and a shift brake. The coupling device is a controllable coupling force, and a friction coupling device coupled by a friction force or an electronic coupling device coupled by an electromagnetic force is preferably used. The friction coupling device is a hydraulic friction coupling that can control the coupling force by hydraulic pressure. Although the apparatus is suitably used, the frictional coupling force may be controlled by pushing the friction material by elastic means such as a diaphragm spring and simultaneously changing the amount of elastic deformation of the elastic means. The transmission may be a continuously variable transmission, a manual transmission, or the like, in addition to a stepped automatic transmission.

A preferred embodiment of the first invention is a torque transmission method for estimating the transmission torque at the time of engagement when the clutch is connected in a power transmission system provided with a clutch for connecting and disconnecting power transmission. And (b) a torque estimating step of determining the coupling torque of the clutch near the boundary between the slip state and the connecting state and making the transmission torque at the time of engagement. The torque estimating step (b) may, as in the second invention, obtain a coupling torque in the vicinity of where the clutch starts to slip, but it may be possible to reconnect the clutch to obtain a coupling torque near the connection, An average value of the plurality of coupling torques may be obtained by repeating the slip state such as increasing or decreasing the connection state and the connected state. It is also possible to estimate the transmission torque using a brake instead of the clutch.

According to a preferred embodiment of the fourth aspect of the present invention, the transmission torque at the time of engagement is determined by using a coupling device provided in the power transmission system of the vehicle, preferably an oscillation clutch, in accordance with the first or second invention. The engine torque is calculated in consideration of the inertia of each part, and the engine torque map, which is a predetermined physical quantity, is calculated based on the engine load (throttle valve opening, fuel injection amount, intake air amount, Excel operation amount, etc.) and engine speed as parameters. And corrected by the calculated engine torque value. As a method of correction, for example, the torque value of the corresponding part of the map is sequentially converted into a method, or as a basic map, various types of forms such as creating a correction map having the same engine load and engine speed as parameters separately are used. It can be adopted. The torque calculation data need not necessarily be a map, and may be a calculation formula or the like. In this case, the torque calculation data may be corrected by adding a correction term by correcting a coefficient of the calculation formula or the like.

Another embodiment of the present invention will be described.

Example 1

An automatic vehicle provided with an oscillation clutch such as a hydraulic friction clutch that can control an engagement force between an engine and a transmission, comprising: (a) engagement force control means for controlling an engagement force of the oscillation clutch, specifically, a clutch hydraulic pressure; (b) a pair of rotational speed detection means for detecting the rotational speed of a member located before and after the oscillation clutch when transmitting power; and (c) the coupling force of the oscillation clutch is reduced by the hydraulic control means. (D) slip determination means for judging on the basis of the detection values of the pair of rotational speed detecting means whether or not the oscillating clutch has started to slip in accordance with the decrease in the engagement force; ) The engagement torque of the oscillation clutch when the oscillation clutch starts to slip is calculated based on the above engagement force, and the engagement torque is released. Accordingly, when the clutch for connecting the torque transmission transmission torque of automatic estimation apparatus for a vehicle characterized in that it has a torque estimating means for a (transmission torque upon engagement).

Example 2

(a) target transmission torque setting means for setting a target transmission torque for mitigating shock during shifting of the stepped automatic transmission based on the transmission torque obtained by the torque estimating means, and (b) combining torque of the oscillating clutch. Torque of the automatic vehicle characterized in that it has a torque down control means for shifting to reduce the torque transmitted to the automatic transmission by controlling feedback of the coupling force control means so that the coupling torque becomes the target transmission torque. Down control device. The engagement torque of the oscillation clutch at the time of slip is the actual transmission torque, and the torque transmitted to the automatic transmission is reduced by reducing the engagement torque of the oscillation clutch as described above, thereby reducing the shift shock. In addition, since the torque transmitted to the automatic transmission is controlled by the combined torque of the oscillating clutch, the torque transmitted to the automatic transmission can be controlled quickly and with high accuracy compared to the engine output control. As transmission torque (transmission torque at the time of coupling) is obtained with high accuracy, shift shock can be prevented with higher accuracy. In addition, the automatic transmission shifts the gear stage automatically according to the driving state.

Example 3

(a) Tire slip detection means used for anti-lock brake system (ABS), TRC (Traction Control System), and (b) ABS and TRC are not used when the slip of the tire is detected by the slip detection means. Or an automatic vehicle having a slip-down torque down control means for slipping the oscillating clutch by reducing the coupling force by the coupling force control means in cooperation with the other, or reducing the transmission torque (coupling torque). Torque down control device. The torque down control means at sleep is, for example, the same as the above (Embodiment 2), and is configured to feedback control the coupling force control means such that the coupling torque coincides with a predetermined target transmission torque. Even in this case, the tire drive torque can be controlled quickly and with high accuracy as compared to the engine output control.

Example 4

The oscillating clutch is a friction clutch, and the friction coefficient (μ) of the friction material is almost constant wet type without being constrained by the change of the slip rotational speed (ΔN), and the friction coefficient (μ) is used in the torque down control at the time of shifting or slipping. A torque down control device for an automatic vehicle, characterized in that constant engagement torque (transmission torque) of the starting clutch is determined. In this case, since the friction coefficient mu is constant, the coupling force or the coupling torque (transmission torque) is obtained using only the additional load such as clutch hydraulic pressure as a parameter, and the calculation is easy, and the transmission torque can be quickly obtained.

Example 5

The oscillating clutch is a friction clutch and a dry type in which the friction coefficient mu of the friction material changes the slip rotation speed ΔN as a parameter. In the torque down control at the time of shifting or slipping, slip rotation is performed according to a predetermined correspondence. A torque down control apparatus for an automatic vehicle, characterized in that a coupling torque (transmission torque) of an oscillating clutch is obtained by obtaining a friction coefficient (μ) corresponding to the speed (ΔN). In this case, the coupling torque (transmission torque) can be obtained with high accuracy irrespective of the change in the friction coefficient mu in accordance with the change in the slip rotational speed ΔN.

Example 6

The oscillating clutch is a hydraulic friction clutch, and the torque estimating means detects the clutch hydraulic pressure when the oscillating clutch starts to slip by a pressure sensor provided in the hydraulic circuit to calculate a coupling force or a coupling torque. The transmission torque estimator of the automatic vehicle, in this case, detects the actual clutch hydraulic pressure, so that the transmission torque at the time of engagement can be estimated with higher accuracy than when using the hydraulic command value.

Example 7

An automatic vehicle provided with a friction type oscillation clutch by an oil pressure between an engine and a continuously variable transmission, comprising: (a) engagement force control means for controlling an engagement force of the oscillation clutch, and (b) the oscillation at power transmission. A pair of rotational speed detecting means for detecting the rotational speed of a member located before and after the clutch; (c) coupling force reduction command means for lowering the coupling force of the oscillating clutch by the hydraulic control means; and (d) Slip determination means for determining, based on the detected values of the pair of rotational speed detecting means, whether or not the oscillating clutch has started to slip in accordance with the decrease in the engagement force, and (e) when the oscillating clutch starts to slip; The coupling torque of the oscillating clutch is calculated based on the above coupling force, and the coupling torque is transmitted at the time of connection of the oscillating clutch (transmitting at the time of coupling). Oak) torque estimating means, (f) slip detection means for tires used for ABS, TRC, etc., and (g) ABS or TRC is not used when the slip of the tire is detected by the slip detection means, or A torque down control device for an automatic vehicle characterized in that it has slipping torque down control means for cooperating with them to lower the coupling force by slipping the oscillating clutch to reduce its transmission torque (coupling torque). . For example, the torque down control means at the time of sleep is formed in accordance with the transmission torque at the time of clutch connection in the same manner as in the above (Example 2), and the coupling force control means is adapted so that the coupling torque coincides with the target transmission torque. Is configured to control feedback.

[Embodiment 8] A torque down control device for an automatic vehicle, characterized in that the torque down control of the third embodiment is performed by using the shift clutch of the stepped automatic transmission instead of the start clutch.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a power transmission device of an automatic vehicle, in which an output of the engine 10 is transmitted to an automatic transmission 14 at a stepped stage via an automatic clutch 12, and further includes a longitudinal reduction device 16. It is transmitted to the drive wheels 18 on the left and right. The auto-start clutch 12 automatically connects and disconnects power transmission between the engine 10 and the automatic transmission 14 in accordance with the driver's shift lever operation, and the like. Corresponding to the clutch of claim 5, for example, as shown in FIG. 3, a hydraulic multi-plate friction clutch and a case connected to the crankshaft 11 (see FIG. 1) of the engine 10 are shown. (20), the disk 24 connected to the input shaft 22 of the automatic transmission 14 so that relative rotation is impossible, and a plurality of friction materials provided in the case 20 and the disk 24 so that relative rotation is impossible, respectively. (26, 28) and a piston (32) for watertight fitting in the case (20) and for engaging the friction materials (26, 28) in accordance with the clutch hydraulic pressure (P) supplied from the flow path (30). The automatic oscillation clutch 12 is configured substantially symmetrically with respect to the center line, and the lower half is omitted from the center line in FIG.

The clutch hydraulic pressure P is configured to be pressure-controlled by the pressure regulating valve 34 using the line hydraulic pressure PL as a basic pressure as shown in FIG. 1, and the pressure regulating valve 34 is a hydraulic command signal supplied from the controller 36. Controlled by SP *. The controller 36 is supplied with a hydraulic signal SP indicating the clutch hydraulic pressure P from the pressure sensor 38 and the crank shafts positioned before and after the automatic start clutch 12 by the pair of rotational speed detecting means 40 and 42 ( 11), the rotational speed signals SNin and SNout indicating the input rotational speed Nin and the output rotational speed Nout, which are rotational speeds of the input shaft 22, are supplied.

The controller 36 includes a microcomputer having a CPU, a RAM, a ROM, and the like, and executes the flowchart shown in FIG. 2 by performing signal processing in accordance with a program stored in advance in the ROM using a temporary storage function of the RAM. do. Fig. 2 shows, for example, a torque down control during the shift of the automatic transmission 14, in particular during down-shift of power-off where shift shock is a problem, and torque due to TRC during slippage of the driving wheel 18. In the down control, execution is started when the torque down command signal is supplied from the shift control apparatus or the TRC in the case of performing the torque down control using the automatic start clutch 12.

ε라면 스탭 S1이하를 반복하여 클러치 유압 P를 미리 정해진 일정한 변화율 ΔP로 저하시키지만, ΔN>ε의 경우에는 스텝 S4 이하를 실행한다.In step S1 of Fig. 2, the hydraulic command signal SP * for outputting the oil pressure P * P-ΔP as low as the constant hydraulic pressure ΔP from the current clutch hydraulic pressure P is output to the pressure regulating valve 34, and the automatic starting clutch 12 Clutch hydraulic pressure P, further improves the coupling force (friction force). The constant hydraulic pressure? P may be determined in advance, but may be set according to a data map, a calculation formula, or the like in accordance with the slip state, the type of shift, the other driving state, or the like. In step S2, the rotational speed difference ΔN = Nin-Nout is calculated based on the rotational speed signals SNin and SNout. In step S3, the slip determination is made based on whether or not the rotational speed difference ΔN is greater than the preset slip determination value ε (≒ 0). Do it. And ΔN

If?, the step S1 or less is repeated to lower the clutch hydraulic pressure P to a predetermined constant change rate? P, but if? N> ?, step S4 or less is executed.

4 shows an example of such a time chart of torque down control, in which the transmission torque of the automatic oscillation clutch 12 is temporarily lowered by TRC, time t1 is the start time of the torque down control, and t2 is a step. The slip determination of S3 is YES. In addition, in the graph of torque, the combined torque T represented by a dashed line represents the combined torque of the automatic oscillation clutch 12, that is, the torque capacity that can be transmitted, and the transmission torque represented by the solid line is actually via the automatic oscillation clutch 12 automatically. It is the torque transmitted to the transmission 14.

In step S4, the clutch hydraulic pressure P at the time of starting slip, that is, when the judgment in step S3 is set as an example, is set as the slip start hydraulic pressure slip, and in step S5, the automatic starting clutch 12 at the start of slip based on the slip starting hydraulic pressure Pslip. The combined torque Tslip of) is calculated according to the following equation. As the clutch hydraulic pressure P set as the slip starting hydraulic pressure slip, when the pressure sensor 38 obtains high reliability with high accuracy, it is desired to use the hydraulic pressure value indicated by the hydraulic signal SP, but the hydraulic command signal SP * output from the controller 36 is desired. It is also possible to use a hydraulic command value indicated by the above, in which case an expensive pressure sensor 38 becomes unnecessary, and the apparatus is inexpensively configured.

Where μ: friction coefficient

n: number of friction surfaces

Df: outer diameter of friction surface

df: inner diameter of friction surface

A: Piston Area =

Dp: Piston Outer Diameter

dp: piston inner diameter

Here, as shown in Fig. 4, the engagement torque Tslip of the automatic starting clutch 12 at the start of the slip is the actual transmission torque when the automatic starting clutch 12 is in the connected state before the slip, that is, at the time of engagement. It corresponds to the transfer torque, and the above steps S1-S5 correspond to one embodiment of the torque estimation method according to claims 1 and 2, wherein step S1 is a coupling force lowering step, steps S2 and S3 are slip determination step, Steps S4 and S5 are torque estimation steps. Further, the series of devices including the controller 36 is an embodiment of the torque estimating apparatus of claim 5, and in the series of signal processing by the controller 36, the portion executing step S1 is a coupling force lowering command means. , The part which executes steps S2 and S3 is slip determination means, and the part which performs steps S4 and S5 is torque estimation means. Moreover, the pressure regulating valve 34 which pressure-regulates the clutch hydraulic pressure P according to the engagement force fall command means of step S1 is corresponded to the engagement force control means. In addition, in the above formula (1), μ · Pslip · A · n is a coupling force of the automatic starting clutch 12 at the start of slip, but when the clutch hydraulic pressure P is substituted in place of the slip start hydraulic pressure Pslip, it is indicated by a dashed-dotted line in FIG. The coupling torque T (including transmission torque at the time of clutch slip) shown is calculated | required.

Subsequently, step S6 is set according to a function g (Tslip) such as an arithmetic expression or data map that is set in advance by using the coupling torque Tslip at the start of the slip, that is, the transmission torque at the coupling when the automatic oscillation clutch 12 is connected. Set the transfer torque Tref. Subsequently, in step S7, the clutch hydraulic pressure P is feedback-controlled while calculating the coupling torque T according to the above formula 1 so that the actual transmission torque of the automatic starting clutch 12, specifically, the coupling torque T becomes the target transmission torque Tref. do. The automatic oscillation clutch 12 of this embodiment is a wet type, and the friction coefficient μ of the friction materials 26 and 28 is a friction coefficient μ to a change in the rotation speed difference (slip rotation speed) ΔN as shown by the solid line in FIG. 5. The coupling torque T can be obtained easily and quickly with high accuracy. However, when higher accuracy is required or when the friction coefficient μ is large with respect to the change in slip rotation speed ΔN, such as a dry clutch, the friction coefficient depends on the function h (ΔN) using the rotation speed difference ΔN as a parameter. It is desirable to allow μ to be set. When the torque down end signal is supplied from the shift control device or the TRC, the execution of step S7 is stopped, and the engagement state of the automatic start clutch 12 is returned to the original state determined according to the engine output or the like. Time t3 of FIG. 4 is the time when the said torque down end signal was supplied.

As described above, the automatic vehicle of the present embodiment lowers the engagement force of the auto-start clutch 12 and intentionally slips, and the coupling torque Tslip of the auto-start clutch 12 is set near the boundary between the slip state and the engaged state (connected state). Although the coupling torque Tslip is regarded as the transmission torque at the time of clutch connection, the target transmission torque Tref of the torque down control is set, but the coupling torque Tslip of the auto-start clutch 12 is obtained by using the slip start hydraulic pressure Pslip. Obtained with high accuracy according to Equation 1, and at the same time, the coupling torque Tslip near the boundary between the slip state and the coupled state is equivalent to the actual transmission torque when the coupled state is engaged. The torque can be estimated with high accuracy.

In addition, in this embodiment, since the coupling torque Tslip at the time of slip start is obtained, for example, operation and control are compared with the case where the clutch hydraulic pressure P is raised thereafter as compared with the case where the coupling torque when connected is obtained as the transmission torque at the time of coupling. It is easy to estimate the transmission torque when combined in a short time. In particular, since the automatic starting clutch 12 of the present embodiment is a hydraulic wet friction clutch, the coupling force can be easily and quickly controlled with high accuracy by the clutch hydraulic pressure P. FIG.

Also in torque down control, since the transmission torque (coupling torque T) of the automatic starting clutch 12 can be controlled by the clutch hydraulic pressure P, the torque transmitted to the automatic transmission 14 as compared to the output control of the engine 10. B) Drive wheel torque can be controlled quickly and with high accuracy, and the transmission torque is estimated to be high accuracy when connected and the target transmission torque Tref is set to high accuracy based on it, so that the control accuracy of the torque down control is improved. Shift shocks and tire slips can be prevented even better.

Next, another embodiment of the present invention will be described.

The automatic start clutch 50 of FIG. 6 is a dry friction clutch, which is used in place of the automatic start clutch 12, and has a flywheel 52 and an input shaft connected to the crankshaft 11 of the engine 10. A clutch disc 54 having a friction material provided at an outer circumferential portion of the clutch disc 54 and a friction material of the clutch disc 54 interposed therebetween, are provided on the opposite side to the flywheel 52 and the fly wheel 52 And a pressure plate 56 which is integrally rotated with the diaphragm spring 58 which adds the pressure plate 56 in a direction approaching the flywheel 52 to press the clutch disc 54. The inner circumferential edge of the diaphragm spring 58 is displaced in the right direction of the drawing through a release fork 62 by an actuator 60 such as an electric motor which functions as a coupling force control means. Reduces the additional load applied to the shutter plate 56 and the clutch binding force is reduced due to friction. In this case, for example, the relationship between the actuation amount of the actuator 60 or the release fork 62 and the added load by the diaphragm spring 58 is set in advance, and the actuator 60 or the release fork 62 is established. Depending on the operating amount of, additional load, and furthermore, the coupling force may be obtained. It is also possible to obtain the coupling force from the relationship between the driving force of the actuator 60 and the added load by the diaphragm spring 58.

Also in the dry automatic oscillation clutch 50, the transmission torque (coupling torque Tslip) at the time of engagement or torque down control can be obtained in the same manner as in the above embodiment, but the friction is performed by the slip rotational speed ΔN. Since the coefficient mu greatly changes, it is desired to set the friction coefficient mu according to the function g (ΔN) when obtaining the combined torque Tslip according to the above equation (1).

In addition, in the above embodiment, the coupling torque Tslip is calculated after the slip determination is performed. For example, as shown in FIG. 7, the clutch hydraulic pressure P is decreased in step R1, and at the same time, the clutch is coupled to the Pslip in the above formula (1). The engagement torque T may be calculated in order by substituting the hydraulic pressure P, and the engagement torque T when the judgment of step R4 is taken as an example may be the engagement torque Tslip at the start of slip, that is, the transmission torque at the engagement. In this case, step R1 is a coupling force lowering step, step R3 and R4 are slip determination steps, and step R2 and R5 are torque estimation steps. In addition, the part which performs step R1 is a coupling force fall command means, the part which performs steps R3 and R4 is a slip determination means, and the part which performs step R2 and R5 is a torque estimation means.

Incidentally, the above embodiment has been described with respect to the torque down control, but for example, the engine torque learning control can be performed as shown in FIG. In step Q1, it is judged whether or not the throttle valve opening degree θth or the vehicle speed V is almost constant normal operation. If normal operation, the torque estimation routine of step Q2 is executed. For example, steps S1-S5 of FIG. 2 or FIG. As described above, the coupling torque Tslip is calculated as the transmission torque when the automatic starting clutch 12 is engaged. In step Q3, it is judged whether or not the learning condition is satisfied, for example, whether or not the throttle valve opening degree θth or the amount of change in the vehicle speed V is less than or equal to the predetermined value during the execution of the torque estimation routine of step Q2. Is satisfied, the engine rotational speed Ne, the throttle valve opening degree θth, and the engine rotational acceleration dNe / dt at that time are read as Step Q4. In step Q5, the engine torque Te is estimated according to Equation 2 considering the inertia amount Ie of the engine 10 and the like. In step Q6, the engine torque Te is parameterized in the engine torque map using the throttle valve opening degree θth and the engine rotational speed Ne as parameters. The engine torque data relating to the throttle valve opening degree θth and the engine rotational speed Ne and the estimated engine torque Te are compared. When the difference is more than a predetermined value, the engine torque data is replaced with the estimated engine torque Te and written.

This embodiment corresponds to an embodiment of the torque calculation data correction method according to claim 4, which is a case of learning and correcting the engine torque map of the torque calculation data book, and is caused by individual differences or disturbances caused by irregular changes in manufacturing. Irrespective of fluctuations, changes over time, the engine torque can always be obtained with high accuracy from the engine torque map. As a result, various controls using the engine torque obtained from the engine torque map, for example, the shift clutch input pressure and the lockup clutch pressure, are executed with higher accuracy.

In the torque estimation routine of step Q2, it is only necessary to calculate the torque Tslip of the automatic oscillation clutch 12, so that, as in the invention described in claim 3, the coupling torque Tslip is calculated to estimate the transmission torque at the time of coupling, and then immediately. Since the slip state of the automatic starting clutch 12 may be terminated and engaged, there is little effect on the transmission torque.

As mentioned above, although the Example of this invention was described in detail based on drawing, this invention can also be implemented with other aspects.

For example, the clutch oscillation P is controlled so that the automatic starting clutch 12 is maintained near the boundary between the slip state and the engaged state, thereby monitoring the engaged torque Tslip at all times, and at the combined torque Tslip when the engine torque map fails. It is also possible to obtain engine torque according to equation (2) or to feedback control the engine 10 using the combined torque Tslip when the torque down control is executed by the output control of the engine 10.

In the above embodiment, the engagement torque Tslip at the start of slip is set based on the slip start hydraulic pressure Pslip or the engagement torque T when the judgment of step S3 in FIG. 2 or step R4 in FIG. 7 is taken as an example. The coupling torque Tslip may be set by correcting the slip starting hydraulic pressure Pslip or the coupling torque T from the amount of decrease ΔP or the rotation speed difference ΔN per cycle of P.

In the above embodiment, the case where the transmission torque of the power transmission system of the engine driving vehicle has been described has been described, but the same may be applied to the case of estimating the transmission torque of the power transmission system of the motor driving vehicle.

Although not illustrated separately, the present invention can be embodied in various forms based on the knowledge of those skilled in the art.

The torque estimation method of the first invention reduces the coupling force of the coupling device provided in the power transmission system, intentionally slips, calculates the coupling torque of the coupling device near the boundary between the slip state and the coupling state (integrated state), and the coupling torque. Although the transmission torque at the time of coupling is estimated based on the coupling torque, the coupling torque of the coupling device is obtained with high accuracy according to well-known formulas from the coupling force and the diameter dimension of the coupling portion, and the boundary between the slip state and the coupling state. Since the coupling torque in the vicinity corresponds to the actual transmission torque in the engaged state, the transmission torque at the time of coupling can be estimated with high accuracy without using an expensive torque sensor. In addition, since the transfer torque at the time of coupling can be estimated only by detecting the presence or absence of slip, if the transfer torque at the time of coupling is only estimated, it hardly affects the transfer torque. Further, in the case of the clutch, the coupling torque at the vicinity of the boundary is used as the transmission torque at the time of engagement. However, in the case of the brake, the transmission torque is calculated at the engagement of the gear ratio using the coupling torque as the reaction force near the boundary.

The second invention is one embodiment in the case of using the clutch of the torque estimation method of the first invention, and the same effects as in the first invention can be obtained. In addition, it is easier to control and control the torque in a short time compared to the case where the coupling torque at the time of connection is transferred to the transmission torque at the time of connection by increasing the coupling force to make the coupling torque starting to slide as the transmission torque at the time of coupling. You can get it. Further, the fifth invention relates to a torque estimating apparatus which can preferably implement the torque estimating method of the second invention, and the same effect as the second invention is obtained.

The third invention hardly affects the actual transmission torque in order to engage the coupling device or the clutch by closing the slip state immediately after the estimation of the transmission torque at the engagement is completed.

The fourth invention corrects the torque calculation data, which is predetermined as a parameter, using the transmission torque estimated at the time of the first invention in order to obtain a torque of a predetermined part related to the power transmission system. The torque of the predetermined part can always be obtained with high accuracy from the torque calculation data without being constrained by individual differences due to changes, fluctuations due to disturbances, changes over time, and the like. This improves the accuracy of the various controls using the torque obtained from the torque calculation data.

Claims (6)

A torque estimating method for estimating a transmission torque during coupling of the power transmission system when the coupling device is coupled in a power transmission system provided with a coupling device capable of controlling coupling force, wherein the coupling force of the coupling device is lowered to intentionally slip and slip Obtaining a coupling torque of the coupling device near a boundary between a state and a coupling state, and estimating a transmission torque during the coupling based on the coupling torque. A torque estimating method for estimating transmission torque at engagement when the clutch is connected in a power transmission system provided with a clutch for connecting and disconnecting power transmission, the torque estimation method comprising: a coupling force lowering step of reducing the engagement force of the clutch at engagement of the clutch; And a slip determination step of determining whether or not the clutch starts to slip in accordance with the decrease in the coupling force, and calculating a coupling torque of the clutch based on the coupling force in the vicinity of the slipping of the clutch, wherein the coupling torque is calculated as the above. A torque estimating method, characterized in that it has a torque estimating step of transmitting torque at the time of coupling. The torque estimating method according to claim 1, wherein a slip state ends and is coupled immediately after the estimation of the transmission torque during coupling is completed. A method of correcting torque calculation data predetermined as a parameter using a predetermined physical quantity to obtain a torque of a predetermined part relating to a power transmission system provided with a clutch for connecting and disconnecting power transmission, the method estimated in accordance with claim 1 Torque calculation data correction method characterized in that for correcting the torque calculation data using the transfer torque when coupled. A torque estimating apparatus for estimating a transmission torque at the time of engagement when the clutch is connected in a power transmission system provided with a clutch for connecting and disconnecting power transmission, comprising: engagement force control means for controlling the engagement force of the clutch, and in the power transmission system; A pair of rotational speed detecting means for detecting the front and rear rotational speeds of the clutch, coupling force lowering command means for lowering the coupling force of the clutch by the coupling force control means when the clutch is engaged, and according to the reduction of the coupling force, A slip determination means for determining whether the clutch has started to slip or not based on the detected values of the pair of rotational speed detecting means, and calculating a coupling torque of the clutch based on the coupling force in the vicinity of the sliding start of the clutch. Lowering the coupling torque to the transmission torque during the coupling. And a torque estimating means. The torque estimating method according to claim 2, wherein a slip state ends and is coupled immediately after the estimation of the transfer torque during coupling is completed.

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