JP3259212B2 - Transmission line pressure control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the variations in the vehicle equipped with automatic transmission with a fluid coupling (such as a torque converter or a fluid coupling ripple grayed) between the engine and the drive shaft
The present invention relates to a speed line pressure control device .

[0002]

2. Description of the Related Art In an automatic transmission for a vehicle, a line pressure is obtained by adjusting a discharge pressure of an oil pump, and the line pressure is supplied to a hydraulic circuit to operate an oil pressure of a torque converter and various transmission elements in a gear type transmission mechanism. Operating hydraulic pressure. Generally, the line pressure of the transmission is determined from the engine output torque (transmission input torque) and the state of the transmission (shift / non-shift, etc.). It is known that the following problems may occur if the line pressure of the transmission is not properly applied.

[0003] At the time of non-shifting, when the speed is too low, the durability is reduced or broken due to slippage of the clutch. When the speed is too high, fuel consumption is deteriorated due to an increase in pump load. In addition, when shifting, if the speed is too low, the durability is reduced or broken due to slippage of the clutch, etc. If the speed is too high, the clutch is suddenly connected, especially when shifting from the 1st to the 2nd speed. Is generated.

Therefore, conventionally, an engine output torque (transmission input torque) is estimated from an operating state parameter of the engine, for example, an intake air amount per unit rotation of the engine. Specifically, the engine output torque Tq is calculated from the intake air flow rate Qa and the engine speed Ne.
In this case, since it is necessary to subtract the torque consumed by the engine itself, the frictional intake air flow rate Qf is determined based on the engine speed Ne, and the engine output torque Tq is obtained from the following equation. Note that K is a constant. Tq = K × (Qa−Qf) / Ne

[0005] Based on the engine output torque Tq, the line pressure is calculated and controlled according to whether the shift is being performed or not, and during the shift, for each type of shift. As described above, by accurately calculating the engine output torque, the controllability of the line pressure control can be improved.

On the other hand, when a part of the engine output torque is consumed by auxiliary equipment such as an air conditioner and the transmission input torque is reduced accordingly, the line pressure becomes too high than an appropriate value, and the line pressure is controlled. May worsen sex.
This significantly deteriorates the shift shock particularly during shifting in a region where the engine output torque is low (for example, the throttle opening is 1/8 or less).

On the other hand, Japanese Patent Application Laid-Open No. 61-223361 discloses an example in which ON / OFF of a switch of an auxiliary device is read and the line pressure is reduced when the switch is ON. Further, Japanese Patent Application Laid-Open No. 6-278506 discloses an example in which the operating torque of accessories is corrected using both the torque converter characteristic and the entire engine performance. In particular,
A capacity coefficient τ is determined from the speed ratio e of the torque converter (see FIG. 6), and a transmission input torque Tp = τ × Ne ² is calculated from the capacity coefficient τ and the engine speed Ne. Is controlled.

[0008]

However, in the former Japanese Patent Application Laid-Open No. 61-223361, the ON / OFF of auxiliary equipment is disclosed.
Although it is described that the line pressure can be controlled irrespective of OFF, there is a problem that a simple ON / OFF switch makes it difficult to perform appropriate correction when the load is not constant like a variable capacity air conditioner.

In the latter Japanese Patent Application Laid-Open No. 6-278506, the torque converter characteristic (capacitance coefficient τ) is determined by the speed ratio e as shown in FIG. 6, but if rotation detection is not performed accurately, appropriate correction is performed. There was no problem. Because, as is clear from FIG. 6, the slope of the characteristic line of the capacitance coefficient τ is steep in the normal range where the speed ratio e is close to 1 (the range of e = 0.8 to 1.0). Unless is calculated, it is difficult to accurately calculate the transmission input torque.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a transmission line pressure control device that realizes more appropriate line pressure control while taking into account auxiliary equipment operating torque as much as possible. Aim.

[0011]

For this purpose, claims 1 to 3
In the invention according to claim 3 , in a vehicle including an automatic transmission with a fluid coupling between the engine and the drive shaft, as shown in FIG. 1, the first torque for calculating the engine output torque from the operating state parameter of the engine. Calculating means, vehicle stop state detecting means for detecting a state in which the engine is running and the transmission is at a position other than the neutral position and the vehicle is stopped, and calculating the transmission input torque from the engine speed in the vehicle stopped state A second torque calculating means for subtracting a transmission input torque calculated by the second torque calculating means from an engine output torque calculated by the first torque calculating means in the vehicle stopped state, Accessory operating torque calculating means for calculating an operating torque for the auxiliary equipment, and an operating torque for the auxiliary equipment based on an engine output torque calculated by the first torque calculating means. A torque correcting means for correcting the engine output torque by subtracting the accessory operating torque calculated by the calculating means, and a line pressure calculating means for calculating a line pressure of the transmission based on the corrected engine output torque. And a line pressure control means for controlling the line pressure of the transmission based on the calculated line pressure to constitute a transmission line pressure control device.

That is, in a state in which the engine is operated and the transmission is at a position other than the neutral position and the vehicle is stopped (for example, a state in which the brake is stopped in the D range), the transmission input torque is calculated from the engine speed. Calculate.
In the vehicle stopped state, the torque can be calculated only by the engine speed, so that the torque can be estimated with high accuracy. This is because the transmission input torque can be calculated with the speed ratio e = 0 in FIG. 6, that is, with the constant capacity coefficient τ. on the other hand,
Since the engine output torque calculated from the operating state parameters of the engine includes the operating torque of accessories,
If the transmission input torque is subtracted from the engine output torque in the same vehicle stop state, the auxiliary equipment operating torque can be calculated.

Assuming that the operating torque of the auxiliary devices in the vehicle stopped state does not change for a while after the vehicle starts,
The engine output torque is corrected by subtracting the accessory operating torque from the engine output torque calculated from the engine operation state parameter, and the transmission line pressure is calculated and controlled based on the corrected engine output torque. . It is to be noted that the shift shock actually deteriorates in a low load region where the throttle opening is about 1/8 or less, and such a shift can be limited to the 1st to 2nd speed shift at the time of starting in practice. ,
The time from the start to the shift is short, and if such a short time, it can be considered that there is no change in the operating torque of the accessories.

The invention according to claim 1 is characterized in that there is provided a means for assuming that the operating torque of the accessories is 0 after a predetermined time has elapsed from the start of the vehicle. That is, taking into account the shift immediately after the start where the controllability of the line pressure becomes a problem, the line pressure is corrected based on the accessory operating torque calculated when the vehicle is stopped only within a predetermined time from the start, and after the predetermined time has elapsed, Auxiliary equipment operating torque is regarded as 0 to prevent a correction error.

The invention according to claim 2 is characterized in that a means is provided for assuming that the operating torque of the accessories is 0 in a region other than a predetermined low load region. That is, the line pressure is corrected based on the accessory operating torque calculated when the vehicle is stopped only in a predetermined low load region where the controllability of the line pressure is a problem,
In the region other than the low load region, the operation torque of the accessories is regarded as 0, and the correction error is prevented.

The invention according to claim 3 is characterized in that there is provided a means for assuming that the operating torque of the accessories is zero at a position other than the predetermined low gear position. That is, taking into account the 1st to 2nd gear shift immediately after the start where the controllability of the line pressure is a problem, the line pressure correction based on the accessory operating torque calculated when the vehicle is stopped only at a predetermined low gear position is performed. At other than the low-speed side gear position, the auxiliary equipment operating torque is regarded as 0, and a correction error is prevented.

According to a fourth aspect of the present invention, the first torque calculating means calculates the torque from a value related to the intake air amount of the engine. Thereby, the engine output torque can be accurately calculated. However, it can be estimated from the throttle opening, the suction negative pressure, and the like. In the invention according to claim 5 , the second
The torque calculation means calculates the torque in proportion to the square of the engine speed. As a result, the transmission input torque can be accurately calculated according to the torque converter characteristics.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment (one example) of the present invention will be described below. Referring to FIG. 2, an automatic transmission 2 is provided on the output side of engine 1. The automatic transmission 2 includes a torque converter 3 as a fluid coupling interposed on the output side of the engine 1, a gear-type transmission mechanism 4 connected via the torque converter 3, and various transmissions in the gear-type transmission mechanism 4. A hydraulic actuator 5 for performing an operation of connecting and releasing elements. The operating oil pressure for the hydraulic actuator 5 is ON / OFF controlled through various electromagnetic valves. Here, a shift electromagnetic valve 6 for automatic shifting is used.
Only A and 6B are shown. Reference numeral 7 denotes an output shaft of the automatic transmission 2.

Here, an oil pump 8 driven by an input shaft of a gear type transmission mechanism is used to obtain a line pressure which is an operating oil pressure for the torque converter 3 and the hydraulic actuator 5, and an orifice 9 and an electromagnetic valve 10 are used. , A pressure modifier valve 11 and a pressure regulator valve 12 are provided. Solenoid valve 10
Is controlled in duty as described below, and a pilot pressure is obtained based on the discharge pressure of the oil pump 8 guided through the orifice 9. Pressure modifier valve 11 amplifies the pilot pressure. The pressure regulator valve 12 regulates the discharge pressure from the oil pump 8 to a line pressure proportional to the pilot pressure from the pressure modifier valve 11 and sends the line pressure to a hydraulic circuit such as the torque converter 3 and the hydraulic actuator 5.

The control unit 13 receives signals from various sensors. The various sensors include the opening TVO of the throttle valve 14 of the intake system of the engine 1.
Is provided with a potentiometer type throttle sensor 15 for detecting the pressure. Further, a crank angle sensor 16 is provided on the crank shaft of the engine 1 or a shaft that rotates in synchronization with the crank shaft. The signal from the crank angle sensor 16 is, for example, a pulse signal for each reference crank angle, and the engine speed Ne is calculated from the cycle thereof.

Further, a hot-wire type air flow meter 17 for detecting an intake air flow rate Qa is provided in an intake system of the engine 1. Further, a vehicle speed sensor 18 for detecting a vehicle speed VSP by obtaining a rotation signal from the output shaft 7 of the automatic transmission 2 is provided. Furthermore, ON / OF of a variable capacity air conditioner (not shown)
An ON / OFF signal of the air conditioner switch 19 for switching F is input.

The control unit 13 is an integrated type having a built-in CPU for engine control (fuel injection and ignition timing control) and a CPU for automatic transmission control. The CPU for automatic transmission control mainly includes a shift control and a line control. And pressure control. The shift control is performed in accordance with the operation position of the select lever. In particular, when the select lever is in the D range, the first to fourth gear positions are automatically set according to the throttle opening TVO and the vehicle speed VSP, and the shift electromagnetic force is set. Valve 6A, 6B
Of the gear type transmission mechanism 4 is controlled via the hydraulic actuator 5 to the gear position.

In the line pressure control, an engine output torque (transmission input torque) Tqsen is calculated according to a torque calculation routine shown in FIG. 3, and based on this, a line pressure PL is calculated according to a line pressure calculation routine shown in FIG. Then, by outputting a duty corresponding to the line pressure PL and driving the electromagnetic valve 10 as a line pressure actuator, an optimum line pressure is obtained. Here, the line pressure can be increased by increasing the duty (valve opening time ratio).

First, the torque calculation routine of FIG. 3 will be described. This routine is executed every predetermined time. In step 1 (indicated as S1 in the figure, the same applies hereinafter)
It is determined whether the gear position is in a D range other than neutral, 2, L, or the like. If it is not neutral, go to step 2.

In step 2, in order to subtract the torque consumed by the engine itself from the intake air flow rate Qa and the engine speed Ne, a frictional intake air flow rate Qf is determined based on the engine speed Ne. From the equation, the engine output torque Tq is calculated. This part corresponds to first torque calculating means. Tq = K ₁ × (Qa−Qf) / Ne where K ₁ is a constant. The engine output torque Tq may be calculated as follows by detecting the suction negative pressure PB. Tq = K _PB × K _HOS × PB K _PB : constant K _HOS : correction coefficient (See map from Ne and PB)

In step 3, it is determined whether or not the vehicle speed VSP = 0. This part corresponds to the vehicle stop state detecting means. [When the vehicle speed VSP = 0] First, the routine proceeds to step 4, where a timer Tim for measuring the elapsed time after the start is reset (Tim = 0). In step 5, it is determined whether or not the air conditioner switch is ON, and if it is ON, the process proceeds to step 6.

In step 6, since the vehicle is stopped,
Based on the square value of the engine speed Ne, the transmission input torque Tp is calculated by the following equation. This part corresponds to the second torque calculating means. Tp = K ₂ × Ne ² Here, K ₂ is a constant and corresponds to the value of the capacity coefficient τ when the speed ratio e = 0 in FIG.

In step 7, the transmission input torque Tp is subtracted from the engine output torque Tq when the vehicle is stopped, and the auxiliary equipment operating torque (air conditioner operating torque) is calculated by the following equation.
Calculate Tphos. This part corresponds to the auxiliary device operating torque calculating means. Tphos = Tq-Tp Thereafter, the process proceeds to step 13 described later. If the air conditioner switch is turned off in the determination in step 5, step 12
To the auxiliary equipment operating torque (air conditioner operating torque) T
phos = 0. Thereafter, the process proceeds to step 13 described later.

[When the vehicle speed is VSP ≠ 0] First, the routine proceeds to step 8, where a timer Tim for counting the elapsed time after the start is counted up (Tim = T
im + 1). In step 9, it is determined whether or not a timer (elapsed time after the start) Tim is equal to or smaller than a predetermined value C. If the timer is equal to or smaller than the predetermined value C, the process proceeds to step 10. Auxiliary equipment operating torque Tphos = 0
Consider In step 10, it is determined whether or not the throttle opening TVO is equal to or smaller than a predetermined value (for example, 1/8 opening). If it is equal to or smaller than the predetermined value, the process proceeds to step 11, but if it exceeds the predetermined value, the process proceeds to step 12. Auxiliary equipment operating torque Tphos = 0
Consider

In step 11, it is determined whether or not the gear position is in the first speed.
os is maintained), but if it is other than the first speed, the routine proceeds to step 12, where it is assumed that the accessory operating torque Tphos = 0.
Here, the steps 9 → 12 correspond to means for assuming that the operating torque of the accessories is 0 after a predetermined time has elapsed from the start of the vehicle, and the steps 10 → 12 correspond to the accessories except for the predetermined low load region. It is equivalent to the means that regards the operating torque as 0,
The portion from 11 to 12 corresponds to means for assuming that the operating torque of the accessories is 0 when the gear is other than the predetermined low gear position. After these, go to step 13.

[Step 13: Correction of Engine Output Torque] In step 13, the auxiliary engine operation torque Tphos is subtracted from the engine output torque Tq to calculate the corrected engine output torque Tqsen according to the following equation. This part corresponds to a torque correction unit. Tqsen = Tq-Tphos If the gear position is neutral in the determination in step 1, the process proceeds to step 14, where Tqsen = 0.

Next, the line pressure calculation routine of FIG. 4 will be described. This routine is also executed every predetermined time.
In step 21, it is determined whether or not a shift is being performed. If the shift is being performed, the process proceeds to step 22, and if the shift is not being performed, the process proceeds to step 23. In step 22, with reference to the table of FIG. 5, according to the type of shift (i.e. the present gear position after shifting gear position), searches the coefficient K ₃ and the offset OF. In step 23, the coefficient K ₃ and the offset OF are set to constant values (KCONS, OFCONS), respectively, because the shift is not being performed.
Set to.

In step 24, the line pressure PL is calculated from the following equation based on the corrected engine output torque (transmission input torque) Tqsen calculated by the torque calculation routine of FIG. This part corresponds to the line pressure calculating means. PL = Tqsen × K ₃ + OF In addition to the above formula, a shift (type) in which the line pressure PL is determined according to the corrected engine output torque Tqsen.
The engine output torque T is calculated using a non-shift-specific table.
The line pressure PL may be searched from qsen.

In step 25, the calculated line pressure PL
Is compared with a predetermined lower limit value PLmin, and PL <PLmin
In the case of (1), in step 26, PL is restricted to PL = PLmin (limiter processing). In step 27, a duty corresponding to the calculated line pressure PL is output to drive the electromagnetic valve 10 as a line pressure actuator,
Obtain optimal line pressure. This part corresponds to the line pressure control means.

[0035]

As described above, claims 1 to 1 are described.
According to the invention according to the third aspect , in a state where the engine is operated and the vehicle is stopped at a position other than the neutral position,
By accurately calculating the input torque of the transmission from the engine speed and calculating the operating torque of accessories based on this, more appropriate line pressure control is realized, taking into account the operating torque of accessories as much as possible. Therefore, it is possible to prevent the shift shock from being deteriorated.

In particular , according to the first aspect of the present invention, the operation torque of the accessories is regarded as 0 after a predetermined time has elapsed from the start of the vehicle. In consideration of the above, the line pressure is corrected based on the accessory operating torque calculated when the vehicle is stopped only within a predetermined time from the start, and after the predetermined time has elapsed, the accessory operating torque is regarded as 0, and a correction error can be prevented.

According to the second aspect of the present invention, the operating torque of the accessories is regarded as zero in a region other than the predetermined low-load region, so that only in the predetermined low-load region where the controllability of the line pressure is a problem. The line pressure is corrected based on the accessory operating torque calculated when the vehicle is stopped, and the correction error can be prevented by regarding the accessory operating torque as 0 outside the low load region.

In particular , according to the third aspect of the present invention, the operating torque of the accessories is regarded as 0 at positions other than the predetermined low-speed gear position, so that 1 → 2 immediately after the start where the controllability of the line pressure becomes problematic. In consideration of the speed change, the line pressure is corrected based on the accessory operating torque calculated when the vehicle is stopped only at a predetermined low gear position, and the accessory operating torque is regarded as 0 at positions other than the low gear position. Correction error can be prevented.

[0039] According to the invention of claim 4, by calculating the torque from the value associated with the intake air amount of the engine,
The effect that the engine output torque can be calculated accurately can be obtained. According to the invention according to claim 5 , by calculating the torque in proportion to the square of the engine speed,
The effect is obtained that the transmission input torque can be accurately calculated in accordance with the torque converter characteristics.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of the present invention.

FIG. 2 is a system diagram showing an embodiment of the present invention.

FIG. 3 is a flowchart of a torque calculation routine.

FIG. 4 is a flowchart of a line pressure calculation routine.

FIG. 5 is a diagram showing a coefficient and offset search table;

FIG. 6 is a diagram showing torque converter characteristics.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Automatic transmission 3 Torque converter 4 Gear type transmission mechanism 5 Hydraulic actuator 6A, 6B Electromagnetic valve for shift 8 Oil pump 10 Electromagnetic valve 11 Pressure modifier valve 12 Pressure regulator valve 13 Control unit 15 Throttle sensor 16 Crank angle sensor 17 Air flow meter 18 Vehicle speed sensor 19 Air conditioner switch

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-278506 (JP, A) JP-A-6-2759 (JP, A) JP-A-6-94113 (JP, A) JP-A-5-94 296886 (JP, A) JP-A-5-280625 (JP, A) JP-A-61-223361 (JP, A) JP-A-2-140066 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48 F02D 45/00

Claims (5)

(57) [Claims] 1. A vehicle having an automatic transmission with a fluid coupling between an engine and a drive shaft, a first torque calculating means for calculating an engine output torque from an operating state parameter of the engine; A vehicle stop state detecting means for detecting a state in which the vehicle stops at a position other than the neutral position; a second torque calculating means for calculating a transmission input torque from an engine speed in the vehicle stop state; In the stopped state, auxiliary equipment operation for calculating auxiliary equipment operation torque by subtracting the transmission input torque calculated by the second torque calculation means from the engine output torque calculated by the first torque calculation means A torque calculating means, and an auxiliary equipment operating torque calculating means calculating from the engine output torque calculated by the first torque calculating means. Torque correction means for correcting the engine output torque by subtracting the operating torque of the auxiliary equipment, line pressure calculation means for calculating the line pressure of the transmission based on the corrected engine output torque, and the calculated line pressure a line pressure control means for controlling the line pressure of the transmission based on further after a predetermined time has elapsed from the start of the vehicle auxiliary machinery operating torr
A transmission line pressure control device comprising: 2. A vehicle having an automatic transmission with a fluid coupling between an engine and a drive shaft, a first torque calculating means for calculating an engine output torque from an operating state parameter of the engine; A vehicle stop state detecting means for detecting a state in which the vehicle stops at a position other than the neutral position; a second torque calculating means for calculating a transmission input torque from an engine speed in the vehicle stop state; In the stopped state, auxiliary equipment operation for calculating auxiliary equipment operation torque by subtracting the transmission input torque calculated by the second torque calculation means from the engine output torque calculated by the first torque calculation means A torque calculating means, and an auxiliary equipment operating torque calculating means calculating from the engine output torque calculated by the first torque calculating means. Torque correction means for correcting the engine output torque by subtracting the operating torque of the auxiliary equipment, line pressure calculation means for calculating the line pressure of the transmission based on the corrected engine output torque, and the calculated line pressure a line pressure control means for controlling the line pressure of the transmission based on, further, the auxiliary devices operating torque other than a predetermined low load range 0
A transmission line pressure control device comprising: 3. A vehicle having an automatic transmission with a fluid coupling between an engine and a drive shaft, a first torque calculating means for calculating an engine output torque from an operating state parameter of the engine, and a transmission operated by the engine. A vehicle stop state detecting means for detecting a state in which the vehicle stops at a position other than the neutral position; a second torque calculating means for calculating a transmission input torque from an engine speed in the vehicle stop state; In the stopped state, auxiliary equipment operation for calculating auxiliary equipment operation torque by subtracting the transmission input torque calculated by the second torque calculation means from the engine output torque calculated by the first torque calculation means A torque calculating means, and an auxiliary equipment operating torque calculating means calculating from the engine output torque calculated by the first torque calculating means. Torque correction means for correcting the engine output torque by subtracting the operating torque of the auxiliary equipment, line pressure calculation means for calculating the line pressure of the transmission based on the corrected engine output torque, and the calculated line pressure a line pressure control means for controlling the line pressure of the transmission based on the further auxiliary devices operating torque other than a predetermined low-speed side gear positions
A transmission line pressure control device comprising: Wherein said first torque calculating means, to any one of claims 1 to 3, characterized in that for calculating the torque from the value associated with the intake air amount of the engine
Transmission line pressure control device as described in the above . Wherein said second torque computing means according to any one of claims 1 to 4, characterized in that in proportion to the square of the engine speed is intended for calculating the torque Transmission line pressure control device.