JPH065097B2 - Hydraulic control of automatic transmission - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a hydraulic control device for an automatic transmission, which is used in combination with an engine having a throttle valve, which can be controlled independently of the movement of an accelerator pedal, in an intake pipe, separately from a throttle valve linked to the accelerator pedal.

[Prior art]

On a road surface having a small friction coefficient such as an icy road or a snowy road, when the vehicle is accelerated, the wheels may slip and the vehicle may be laterally swung. In order to prevent such a state, for example, the slip degree is detected from the difference between the front wheel rotation speed and the rear wheel rotation speed of the wheel, and the ignition timing and the air-fuel ratio are controlled according to the slip degree. A control method for reducing the engine output has been considered. Also, as a slip control device for specifically executing this control, a sub-slottle valve is provided in series with the conventional throttle valve that operates in conjunction with the accelerator pedal in the intake pipe of the engine. A slip control device has been disclosed in which the intake air amount can be controlled independently of the accelerator opening by opening and closing in response to a command from a computer (Japanese Patent Application No. 59-18476).
8).

[Problems to be Solved by the Invention]

When the engine having two or more throttle valves in the intake pipe of the engine and the automatic transmission are used in combination as described above, the control hydraulic pressure in the hydraulic control device of the automatic transmission is controlled by the first throttle valve. Problems may occur when the mechanical or electrical regulation is made according to the opening. That is, when the opening degree of the second throttle valve is lower than that of the first throttle valve, the engine output naturally lowers than the output regulated by the opening degree of the first throttle valve when the second throttle valve is fully opened. If the hydraulic pressure on the automatic transmission side is regulated by the opening degree of the first throttle valve, the control hydraulic pressure will be higher than the actual output of the engine, which will increase gear shift shocks and unnecessary oil pumps. Power loss will increase. Further, if the hydraulic pressure is adjusted to a low level in anticipation of such a state, the control hydraulic pressure becomes low when both are in the fully opened state, which may cause a problem in the durability of the friction engagement device. become. Such a problem similarly occurs even when the control hydraulic pressure of the automatic transmission is mechanically or electrically defined according to the opening degree of the second throttle valve.

[Object of the Invention]

The present invention has been made in view of such a problem, and even in an automatic transmission used in combination with an engine having two or more throttle valves in the intake pipe of the engine, the actual engine output is always maintained. It is possible to execute the optimum hydraulic pressure control that meets the above conditions, and thus prevent an increase in gear shift shock and power loss in the oil pump that occur due to the hydraulic pressure being adjusted higher than the actual engine output. Then
Also, to provide a hydraulic control device for an automatic transmission, which can prevent the durability of the friction engagement device from being lowered due to the hydraulic pressure being adjusted to be lower than the actual engine output. With the goal.

[Means for solving problems]

The first aspect of the present invention relates to a hydraulic control device for an automatic transmission, which is used in combination with an engine having a throttle valve that is independently controllable from the movement of an accelerator pedal in the intake pipe and is provided separately from a throttle valve linked to the accelerator pedal. As shown in FIG. 1 (A), the means for obtaining the equivalent throttle opening for the engine from the opening of each throttle valve, and the hydraulic control device for the automatic transmission depending on the equivalent throttle opening. And a means for adjusting the control hydraulic pressure therein to achieve the above object. The second aspect of the present invention is the hydraulic pressure of an automatic transmission used in combination with an engine having a throttle valve that is controllable independently of the movement of an accelerator pedal in an intake pipe in series with a throttle valve linked to the accelerator pedal. In the control device, as shown in the outline of FIG. 1 (B), depending on the means for discriminating the throttle valve having the lowest opening degree and the opening degree of the throttle valve having the lowest opening degree, By providing a means for adjusting the control hydraulic pressure in the hydraulic control device of the automatic transmission, the above object can be achieved with a simple configuration without performing complicated calculation.

[Action]

In the first aspect of the present invention, the so-called equivalent throttle opening for the engine is obtained from the opening of each throttle valve in the intake pipe, and the control hydraulic pressure in the hydraulic control device of the automatic transmission is adjusted depending on the equivalent throttle opening. Because,
It is possible to perform hydraulic control that matches the actual engine output. If two throttle valves are arranged in parallel,
Assuming that the opening of the first throttle valve is θ ₁ and the opening of the second throttle valve is θ ₂ , the equivalent throttle opening θ _P is Can be found at. Further, when two throttle valves are arranged in series, the equivalent throttle opening θ _S is Can be found at. On the other hand, in the second aspect of the present invention, only when the throttle valve in the intake pipe is arranged in series, the throttle valve having the lowest opening degree is first determined, and the throttle valve having the lowest opening degree is detected. Since the control hydraulic pressure in the hydraulic control device of the automatic transmission is adjusted depending on the opening, the hydraulic control that is roughly matched to the actual engine output is executed without calculating the complicated equivalent throttle opening. can do. That is, when the throttle valves are arranged in series, the intake air amount is mainly determined by the opening degree of the throttle valve having the lowest opening degree. Therefore, in this case, even if the control oil pressure is determined based on the lowest opening degree,
The configuration can be simplified because there is not much error and there is no need to calculate the equivalent throttle opening. In the first and second inventions, a preferred embodiment is that the control hydraulic pressure is a line pressure. Further, preferably, the control hydraulic pressure is a hydraulic pressure for line hydraulic control. Further, it is preferable that the control hydraulic pressure is a hydraulic pressure in an oil passage immediately before the friction engagement device in the hydraulic control device. Further, it is preferable that the control hydraulic pressure is a hydraulic pressure applied to a back pressure chamber of an accumulator arranged in the hydraulic control device. As described above, the present invention does not limit the type of hydraulic pressure to be regulated. A preferred embodiment is that the pressure adjusting means uses a so-called solenoid proportional valve. Further, it is preferable that the pressure adjusting means uses a so-called duty valve. When the control oil pressure is adjusted according to the opening degree of the throttle valve having a low opening degree as in the second aspect of the invention, the throttle valve is controlled by a mechanical structure in the same manner as in the conventional case, and the throttle valve generates the throttle valve. It is also relatively easy to control the line hydraulic pressure according to the throttle pressure. However, when the equivalent throttle opening is obtained and the control hydraulic pressure in the hydraulic control device is adjusted depending on the equivalent throttle opening as in the first aspect of the invention, a means for obtaining the equivalent throttle opening is used as a mechanical means. Configuration is extremely difficult. Therefore, it is rational to regulate the pressure by using the solenoid proportional valve or the duty valve as described above, and high pressure regulation accuracy can be secured.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 is a schematic configuration diagram showing an engine periphery, an automatic transmission, and a wheel portion of a vehicle to which an embodiment of an automatic transmission hydraulic control device according to the present invention is applied. In the figure, 10 is an engine, 12 is a piston, 14 is a spark plug, 16 is an intake valve, 18 is an exhaust valve, 20 is a fuel injection valve, 22 is a surge tank, 24 is an air flow meter, and 26 is an air cleaner. . In the intake pipe between the air flow meter 24 and the surge tank 22, a DC motor 30 is driven in series with a first throttle valve 28, which is conventionally provided and adjusts an intake air amount in conjunction with an accelerator pedal 26. As with the first throttle valve 28, a second throttle valve 32 for adjusting the intake air amount is provided. On the other hand, 50 to 56 indicate wheels of the vehicle. Reference numerals 50 and 52 denote the left and right drive wheels for driving the vehicle by transmitting the power of the engine 10 through the automatic transmission 58, the propeller shaft 60 and the like. Also 54 and 56
Shows left and right driven wheels that are rotated as the vehicle travels. The left and right driven wheels 54 and 56 are provided with driven wheel speed sensors 80 and 82 for detecting their rotational speeds, respectively, and the automatic transmission 58 is provided with left and right drive wheels 50 and 52. A drive wheel speed sensor (specifically, an output shaft rotation speed sensor of the automatic transmission) 84 for detecting the average rotation speed is provided. As shown in FIG. 3, Traction Computer A
Is an accelerator sensor 8 provided on the accelerator pedal 26.
6, the second throttle sensor 87 provided on the second throttle valve 28, the left and right driven wheel rotation speed sensors 80, 82,
Each signal of the output shaft rotation speed sensor 84 of the automatic transmission is input so that maximum acceleration can be obtained without causing an acceleration slip during vehicle acceleration, that is, the drive wheels 50, 52 and the driven wheels 54, 56. The second so that the rotation speed difference is constant.
The feedback control of the DC motor 30 for adjusting the opening degree of the throttle valve 32 is executed. The engine control computer B includes a first throttle sensor 88 provided in the first throttle valve 28,
Signals from the second throttle sensor 87, an engine speed sensor (specifically, a crank angle sensor) 90, etc. are input to the ignition plug 14 and the fuel injection valve 20 so that the ignition timing and the fuel injection amount are optimal. Control. The automatic transmission computer C includes a signal from the output shaft rotation speed sensor 84 and the first and second throttle sensors 8
Each signal such as 8, 87, etc. is input, and the shift solenoid of the hydraulic control device D is controlled so as to automatically switch the shift stage according to a preset shift map, and the line hydraulic pressure of the hydraulic control device D is controlled. Solenoid proportional valve S to control the
_The load current _IP is output to _D. The control of the line hydraulic pressure by the solenoid proportional valve S _D in the hydraulic control device D is performed as follows. FIG. 4 shows a main part of the hydraulic control device D. In the figure, S _D is the solenoid proportional valve, 102 is a pump,
103 is the primary regulator valve, 104 is 1-
2 shift valve, S ₂ is the shift solenoid valve, 106 is a manual valve operated by a driver, 107 is a transient when hydraulic pressure is supplied to and discharged from a brake B ₂ which is one of friction engagement devices. The accumulators for controlling the characteristics are shown respectively. The solenoid proportional valve S _D is a well-known one in itself, and is composed of spools 109 and 110, a coil 108, a spring 113, a plunger 111, and the like. Spool 110
And the plunger 111 are meshed with each other so as to be movable in the axial direction. Coil 108, plunger 111 according to the load current _{I P} from the automatic transmission computer C,
Therefore, a force F _C in the downward direction in the figure is exerted on the spool 110.
On the other hand, the spring 113 exerts a force F _{S in the} opposite direction on the spool 110. Also, pump 1 is installed in port 114
The discharge pressure of 02 is acting. Ports 115 and 116
Pθ is the hydraulic pressure that acts on the land 109 of the spool 109.
If the face area of A is A ₁ , then Pθ can be calculated by the equation (1). Pθ = (F _S −F _C ) / A ₁ (1) Therefore, by controlling the downward force F _C in the figure generated by the coil 108, P generated at the port 115 is controlled.
θ can be controlled to an arbitrary value of 0 to F _S / A ₁ . This hydraulic pressure Pθ corresponds to the throttle pressure generated by a throttle valve that is conventionally mechanically driven by a spool corresponding to the throttle opening via a normal cam, and is a primary regulator valve. It acts on the port 119 as a control hydraulic pressure of the line hydraulic pressure generated by 103. In the primary regulator valve 103, the line hydraulic pressure PL is generated according to the value of the control hydraulic pressure Pθ by the same operation as in the conventional case. As a result, by controlling the load current I _P to Yotsute coil 108 with a command end automatic transmission computer C, it becomes possible to arbitrarily control the line pressure PL. Note that the primary regulator valve 1
The pressure regulation relational expression in No. 03 is shown in (2). _{PL = {F S2 + (B} 2 + B 3) P R + B 2 Pθ} / B 1 ... (2) _{where, F S2} is acting force of the spring _120, B 1 ~B
₃ is the land 121, 122 of the spool 123, 124,
It is 125 face area. Further, the land 12 when _{P R} is the Maniyuaru valve 106 is in the reverse range
The line hydraulic pressure applied to 2 and 125. Next, the friction engagement device will be described. here,
The brake B ₂ will be described as a representative. The signal pressure of the shift solenoid valve S ₂ acts on the port 126 of the 1-2 shift valve 104. Therefore,
The spool 127 of the 1-2 shift valve 104 slides from right to left in the figure according to ON / OFF of the shift solenoid valve S ₂ . Sliding to the right is due to the force F _{S3 of the} spring 128. At this time, the ports 133 and 129 of the 1-2 shift valve 104 are connected. The line oil pressure PL from the port 130 of the manual valve 106 acts on the port 129 in the D (drive) range. That is, the spool 131 of the manual valve 106
The ports 130, 129, and 133 are connected at the D range selection position. On the other hand, the port 133 is connected to the brake B ₂ via the oil passage 135 and the check valve 134. Therefore, in the D range, the line hydraulic pressure PL is supplied to and discharged from the brake B ₂ by turning on and off the shift solenoid valve S ₂ . The accumulator 107 is connected to the oil passage 135 to control the transient hydraulic pressure level when the line hydraulic pressure PL is supplied to and discharged from the brake B ₂ . The hydraulic pressure P _B2 during the operation of the accumulator 107 is determined depending on the line hydraulic pressure PL applied as the back pressure as shown in the following equation. P _B2 = F _S4 + (C ₁ −C ₂ ) PL / C ₁ (3) Here, F _S4 is the acting force of the spring 136, C ₁ , C
₂ is the face area of the two lands of the accumulator piston 137. By controlling the control oil pressure Pθ by the load current control to the solenoid proportional valve S _{D according} to the above equations (1) to (3), the oil pressure P _B2 to the brake B ₂ is arbitrarily controlled including the transient time. It's ready. FIG. 5 shows a control flow in the automatic transmission computer C. First, in steps 202 to 206, the output shaft rotation speed N ₀ of the automatic transmission, the opening θ ₁ of the first throttle valve 28,
The opening θ ₂ of the second throttle valve 32 is read. At step 208, the equivalent throttle opening θ is calculated by the above-mentioned calculation formula. F of step 210 is a flag for flow control. Since it is initially set to zero, step 212
Then, the shift judgment is performed based on the output shaft rotation speed N ₀ and the throttle opening θ ₁ of the first throttle valve 28. Here, the opening degree θ ₁ of the first throttle valve 28 is used in the gear shift judgment because the opening degree θ ₂ of the second throttle valve 32 is converged by detecting the slip amount of the driving wheels 50 and 52, for example. Since it is used to control the engine output as described above, it may be opened and closed in a short cycle. Therefore, the opening θ _{2 of} this second throttle valve 32 or this θ ₂ is taken into consideration. This is because if the shift determination is performed using the equivalent throttle opening θ, the shift may be frequently performed. If the gear shift is determined in step 212, the gear shift output is performed in step 214, and in step 216, the equivalent throttle opening θ, the selected position of the pattern select switch (economy running E pattern and power running P pattern), and the gear shifting. The solenoid proportional valve _SD depending on the type
The load current I _P to Then, step 22
The load current I _P obtained in step 216 is output until a certain time (time when shifting is considered to be completed) T _S elapses via 0, 224, and when the time elapses, the flag F is set to zero, and in step 218. The obtained load current I _P is changed and output (step 226). On the other hand, when it is determined in step 212 that there is no gear shift, the routine proceeds to step 218, where the load current I _P is determined according to the equivalent throttle opening θ, the output shaft rotation speed N ₀ , and the gear stage at that time, and the step 226 Go to. It should be noted that the steps 216 and 2 are shown in FIGS.
An example of a map for obtaining the load current I _P at 18 will be shown. In both figures, the unit of the load current I _P is ampere. In the above embodiment, the example in which the second throttle valve is provided for the purpose of controlling the slip of the vehicle is shown, but in the first and second inventions, the purpose of providing the second throttle valve is described. Is not limited. Also, the second, third ...
-The number of throttle valves is not limited. In the first aspect of the invention, it is not limited whether the second and third slot valves are arranged in parallel or in series. Further, in the above embodiment, in controlling the hydraulic pressure in the hydraulic control device, the equivalent opening θ of the opening θ ₁ of the first throttle valve and the opening θ ₂ of the second throttle valve is calculated. Then, the hydraulic pressure is determined based on the equivalent opening degree θ (first invention). However, when the first throttle valve and the second throttle valve are arranged in series as described above, In general, since the engine output is governed by the throttle valve having the smaller throttle opening, the magnitudes of θ ₁ and θ ₂ may be compared, and the hydraulic control may be performed depending on the smaller one. (Second invention). By doing so, the initial object of the present invention can be substantially achieved without performing a complicated equivalent opening degree calculation.

【The invention's effect】

As described above, according to the present invention, even when there are a plurality of throttle valves, it is possible to adjust the control hydraulic pressure in the hydraulic control device of the automatic transmission to a hydraulic pressure that matches the actual engine output. The excellent effect that the shift control of the automatic transmission can be performed by the hydraulic pressure that has a small shock, the power loss of the pump is small, and the durability of the friction engagement device is sufficiently ensured. can get.

[Brief description of drawings]

1 (A) and (B) are block diagrams showing the gist of the first and second inventions, respectively, and FIG. 2 is a slip control device to which a hydraulic control device for an automatic transmission according to the present invention is applied. FIG. 3 is a schematic block diagram showing an engine periphery, an automatic transmission, and a wheel portion of a vehicle equipped with a vehicle, FIG. 3 is a block diagram showing an input / output relationship in the apparatus of the above embodiment, and FIG. FIG. 5 shows a partial hydraulic circuit diagram in the hydraulic control device.
6 and 7 are flow charts showing a control routine in the automatic transmission computer, and are diagrams showing an example of a map for obtaining the load current I _P in the routine. A ... Traction computer, B ... Engine computer, C ... Automatic transmission computer, D ... Hydraulic control device, _SD ... Electromagnetic proportional valve, 28 ... First slot valve, 32 ... Second slot valve, 58 ... Automatic transmission .

Claims (8)

[Claims] 1. A hydraulic control device for an automatic transmission, which is used in combination with an engine having a throttle valve, which is controllable independently of the movement of an accelerator pedal, in an intake pipe and which is provided separately from a throttle valve linked to the accelerator pedal. A means for obtaining an equivalent throttle opening for the engine from the opening of each throttle valve, and a means for adjusting the control hydraulic pressure in the hydraulic control device of the automatic transmission depending on the equivalent throttle opening. A hydraulic control device for an automatic transmission, which is characterized in that 2. The hydraulic control device for an automatic transmission according to claim 1, wherein the control hydraulic pressure is a line hydraulic pressure. 3. The hydraulic control device for an automatic transmission according to claim 1, wherein the control hydraulic pressure is a hydraulic pressure for line hydraulic control. 4. The hydraulic control device for an automatic transmission according to claim 1, wherein the control hydraulic pressure is a hydraulic pressure in an oil passage immediately before a friction engagement device in the hydraulic control device. 5. The hydraulic control device for an automatic transmission according to claim 1, wherein the control hydraulic pressure is a hydraulic pressure applied to a back pressure chamber of an accumulator arranged in the hydraulic control device. 6. The hydraulic control device for an automatic transmission according to claim 1, wherein the pressure adjusting means uses an electromagnetic proportional valve. 7. The hydraulic control device for an automatic transmission according to claim 1, wherein the pressure adjusting means uses a duty valve. 8. A hydraulic control device for an automatic transmission, which is used in combination with an engine having a throttle valve, which is controllable independently of the movement of an accelerator pedal, in an intake pipe in series with a throttle valve linked to the accelerator pedal. A means for discriminating the throttle valve having the lowest opening degree, and means for regulating the control hydraulic pressure in the hydraulic control device of the automatic transmission depending on the opening degree of the throttle valve having the lowest opening degree. A hydraulic control device for an automatic transmission, comprising: