JPS62215156A - Oil pressure controlling device for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent increase in the shock of speed change and the power loss of an oil pump and the like by regulating the controlling oil pressure of an automatic transmission to be an oil pressure suited to an actual engine output even in an engine having plural throttle valves. CONSTITUTION:A traction computer A receives the signals of an accelerator sensor 86, a second throttle sensor 87, right and left driven wheel rotating speed sensors 80, 82, an output shaft rotating speed sensor 84 for automatic transmission, etc., and carries out the feedback control of a DC motor for adjusting the opening of a second throttle valve so as to obtain the maximum acceleration without causing an acceleration slippage when accelerating a vehicle. An engine control computer B receives the signals of sensors 88, 87, an engine speed sensor 90, etc., and controls an ignition plug and a fuel injection valve. An automatic transmission computer C receives the signals of the sensors 84, 88, 87 and controls the shifting solenoid of a oil pressure control device D while outputting a load current to its electromagnetic proportional valve SD.

Description

[Detailed description of the invention] [Industrial application field]

The present invention is directed to an improvement in a hydraulic control device for an automatic transmission used in combination with an engine having at least two throttle valves.

[Conventional technology]

When accelerating a vehicle on a road surface with a small coefficient of friction, such as an icy road or a snow-covered road, the wheels may slip and the vehicle may be swayed laterally. To prevent this situation, for example, the degree of slip is detected from the difference between the front wheel rotation speed and the rear wheel rotation speed, and the ignition timing and air-fuel ratio are controlled according to this degree of slip. Control methods that reduce engine output are being considered. In addition, as a slip control device to specifically execute this control, a sub-throttle valve is provided in series with the throttle valve, and by opening and closing this sub-throttle valve, the intake air ■ is controlled independently of the accelerator opening degree. A slip control device is disclosed (Japanese Patent Application No. 59-184).
768).

[Problems to be solved by the invention]

When an engine having two or more throttle valves is used in combination with an automatic transmission, the control oil pressure in the hydraulic control device of the automatic transmission is controlled according to the opening degree of the first throttle valve, as in the past. Problems may occur if mechanically or electrically specified. That is, if the opening degree of the second throttle valve is lower than that of the first throttle valve, the engine output will naturally be lower than the output specified by the opening degree of the first throttle valve when the second throttle valve is fully open. If the oil pressure on the automatic transmission side is regulated by the opening of the first throttle valve, the control oil pressure will be higher than the actual output of the engine, resulting in an increase in gear shift shock and unnecessary use of the oil pump. power loss will increase. Also, if the oil pressure is uniformly adjusted to a low level in anticipation of such a situation, the control oil pressure will be low when both are fully open, which may cause problems with the durability of the friction engagement device. become. Such a problem similarly occurs even if the control oil pressure of the automatic transmission is mechanically or electrically regulated in accordance with the opening degree of the second throttle valve.

[Purpose of the invention]

The present invention was made in view of these problems, and even in an automatic transmission used in combination with an engine having two or more throttle valves, the present invention always provides an optimal transmission that matches the actual engine output. It is possible to perform hydraulic control, thus preventing an increase in gear shift shock and power loss in the oil pump caused by adjusting the hydraulic pressure to a level higher than the actual engine output, and also preventing the actual engine output from increasing. It is an object of the present invention to provide a hydraulic control device for an automatic transmission that can prevent a decrease in durability of a frictional engagement device caused by regulating the hydraulic pressure to a lower level than the conventional hydraulic pressure.

[Means to solve the problem]

The first invention is a hydraulic control system for an automatic transmission used in combination with an engine having at least two throttle valves, as shown in FIG. 1(A). The above object has been achieved by providing means for determining the equivalent throttle opening for a given throttle opening, and means for adjusting the control hydraulic pressure within the hydraulic control device depending on the equivalent throttle opening. Further, the second invention provides a hydraulic control system for an automatic transmission used in combination with an engine having at least two throttle valves arranged in series, as shown in FIG. 1(B). By providing a means for determining the throttle valve having the lowest opening degree, and a means for regulating the control hydraulic pressure in the hydraulic control device depending on the opening degree of the throttle valve having the lowest opening degree, The above object can be achieved with a simple configuration without performing complicated calculations.

[Effect]

In the first invention, the so-called equivalent throttle opening for the engine is determined from the opening of each throttle valve, and the control hydraulic pressure in the hydraulic control device is regulated depending on this equivalent throttle opening. It is possible to perform hydraulic control commensurate with the output. In addition, if two throttle valves are arranged in parallel,
When the opening degree of the first throttle valve is 01 and the opening degree of the second throttle valve is 62, the equivalent throttle opening degree θP is:
, 24 Q, 2. Furthermore, when two throttle valves are arranged in series, the equivalent throttle opening θS is 4 1 +1/θ
24). On the other hand, in the second invention, only when the throttle valves are arranged in series, the throttle valve with the lowest opening degree is first determined, and the opening degree of the throttle valve with the lowest opening degree is determined. Since the control hydraulic pressure in the hydraulic control device is regulated accordingly, it is possible to execute hydraulic control that substantially matches the actual engine output without having to calculate the equivalent equivalent throttle opening degree. 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 in the lowest opening state. Therefore, in this case, there is not much error even if the control oil pressure is determined based on the lowest opening degree, and
The configuration can be simplified by eliminating the need to calculate the equivalent throttle opening. In the first and second aspects of the invention, a preferred embodiment is that the control oil pressure is line pressure. Preferably, the control oil pressure is oil pressure for line oil pressure control. Preferably, the control hydraulic pressure is a hydraulic pressure in an oil passage immediately before the frictional engagement device in the hydraulic control device. Preferably, the control hydraulic pressure is a hydraulic pressure applied to a back pressure of an accumulator disposed within the hydraulic control device. In this way, the present invention does not limit the type of hydraulic pressure to be regulated. Further, a preferred actual IM aspect is that the pressure regulating means uses a so-called electromagnetic proportional valve. Preferably, the pressure regulating means uses a so-called duty valve. As in the second invention, when regulating the control hydraulic pressure according to the opening degree of a throttle valve with a low opening degree, the throttle valve is controlled in the same manner as before using a mechanical structure, and the throttle valve generated by this throttle valve is It is also possible to control the line oil pressure according to the pressure relatively easily. However, when the equivalent throttle opening is determined and the control oil pressure in the hydraulic control device is adjusted depending on the equivalent throttle opening as in the first invention, the means for determining the equivalent throttle opening is mechanically controlled. It is extremely difficult to configure it in a practical manner. Therefore, it is reasonable to regulate the pressure by using an electromagnetic proportional valve or a duty valve as described above, and high precision in pressure regulation can be ensured.

【Example】

Embodiments of the present invention will be described in detail below based on the drawings. FIG. 3 is a schematic configuration diagram showing the engine surroundings, automatic transmission, and wheel portions of a vehicle to which an embodiment of the 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,
26 each represent an air cleaner. The intake passage between the air 70 meter 24 and the surge tank 22 is provided with a conventional first throttle valve 28 that is driven by a DC motor 30 and is connected in series with a first throttle valve 28 that adjusts the amount of intake air in conjunction with the accelerator pedal 26. Similarly to the first throttle valve 28, a second throttle valve 32 is provided which adjusts the amount of intake air. On the other hand, 50 to 56 indicate wheels of the vehicle. 50 and 52, the power of the engine 10 is transmitted to an automatic transmission 58;
The power is transmitted through the propeller shaft 60 and the like, and left and right drive wheels for driving the vehicle are shown. Further, 54 and 56 indicate left and right driven wheels, respectively, which 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. A driving wheel speed sensor (specifically, an output shaft rotational speed sensor of an automatic transmission) 84 is provided to detect the average rotational speed. As shown in Figure 3, the traction computer △
is the accelerator sensor 8 provided on the accelerator pedal 26.
6. A second throttle sensor 87 provided on the second throttle valve 28, left and right driven wheel rotational speed sensors 80, 82,
Each signal from the output shaft rotational speed sensor 84 of the automatic transmission is input, and the driving wheels 50.52 and the driven wheels 54.56 are adjusted so as to obtain maximum acceleration without causing acceleration slip when the vehicle accelerates. The second
Feedback control of the DC motor 30 to adjust the opening degree of the throttle valve 32 is executed. The engine control computer B includes a first throttle sensor 88 provided at the first throttle valve 28;
Second throttle sensor 87, engine rotation speed sensor (
Specifically, a signal from a crank angle sensor) 90 or the like is input, and the spark plug 14 and fuel injection valve 20 are controlled so that appropriate ignition timing and fuel injection amount are achieved. The automatic transmission 1-1 viewer C receives the signal from the output shaft rotational speed sensor 84 and the first and second throttle sensors 8.
Each signal such as 8.87 is input and controls the shift solenoid of the hydraulic control device and the line oil pressure of the hydraulic control device in order to automatically change gears according to a preset shift map. In order to do so, the solenoid proportional valve S
Load current Ip is output to o. The line oil pressure is controlled by the electromagnetic proportional valve So in the hydraulic control device @D as follows. FIG. 4 shows the main parts of this hydraulic control device. In the figure, So is the electromagnetic proportional valve, 102 is a pump,
103 is the primary regulator valve, 104 is 1-
2 shift valve, S2 is the shift solenoid valve, 106 is a manual valve operated by the driver, 107 is one of the frictional engagement devices, and controls transient characteristics when hydraulic pressure is supplied to and discharged from the brake 82. The accumulators for each are shown. The electromagnetic proportional valve So is well known in itself, and is formed by a spool 109, 110, a coil 108, a spring 113, a plunger 111, and the like. Spool 110
The plunger 111 and the plunger 111 are meshed so as to be integrally movable in the axial direction. The coil 108 is connected to the plunger 111 according to the load current 1p from the automatic transmission computer C.
Therefore, a force Fc is applied to the spool 110 in a downward direction in the figure. On the other hand, the spring 113 exerts a force, FS, on the spool 110 in the opposite direction. Further, the discharge pressure of the pump 102 acts on the port 114. ports 115 and 11
6 is Pθ, and land 10 of sprue 109 is
If the face area of 9A is A1, Pθ can be found by equation (1). Pθ=(Fs-Fc)/A1 ・”(1) Therefore,
By controlling the force Fc generated by the coil 108 in the downward direction in the figure, Pθ generated at the port 115 is reduced to O=
Fs/A1 can be controlled to any value. Conventionally, this oil pressure Pθ corresponds to the throttle pressure generated by a throttle valve whose spool can be mechanically driven via a cam in response to the throttle opening, and is the same as the throttle pressure generated by the primary regulator valve 103.
It acts on the port 119 as hydraulic pressure for controlling the line hydraulic pressure generated by the hydraulic pressure. In the primary regulator valve 103, the line oil pressure PL is generated according to the value of the control oil pressure Pθ by the same operation as the conventional one. As a result, by controlling the load current Ip to the coil 108 in accordance with a command from the automatic transmission computer C, the line oil pressure PL can be arbitrarily controlled. Note that the pressure regulation relational expression for the primary regulator valve 103 is shown in equation (2). PL= (Fs 2 + (B 2-83 ) PR+
B2Pθ)/B1...(2) Here, Fs
2 is the acting force of the spring 120, and 81 to B3 are the face areas of the lands 121.122.125 of the spool 123.124. Also, PR is manual valve 106
lands 122 and 125 when is in reverse range.
is the line oil pressure applied to the Next, the relationship between the frictional engagement devices will be explained. here,
The brake B2 will be explained as a representative example. The signal pressure of the shift solenoid valve S2 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 in response to ON-OFF of the shift solenoid valve S2. The sliding to the right is due to the force Fss of the spring 128. At this time, ports 133 and 1 of the 1-2 shift valve 104
29 is 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 ports 130, 129, and 133 are connected to each other at the D range selection position of the spool 131 of the manual valve 106. On the other hand, the port 133 includes an oil passage 135 and a check valve 134.
It is connected to brake B2 via. Therefore, in the D range, the shift solenoid valve S2
Line oil pressure PL to brake B2 due to 0N-OFF of
is supplied and discharged. An accumulator 107 is connected to the oil passage 135, and controls the transient oil pressure level when the line oil pressure PL is supplied to and discharged from the brake B2. The oil pressure PE12 during operation of the accumulator 107 is determined depending on the line oil pressure PL applied as back pressure, as shown by the following equation. PEI2=F! 34 + (C+ -02)PL/
C+...(3) Here, FS4 is the acting force of the spring 136, C1, C
2 is the face area of the two lands of the accumulator piston 137. From the above equations (1) to (3), by controlling the control oil pressure Pθ by controlling the load current to the electromagnetic proportional valve So, the oil pressure per day 2 to the brake B2 can be controlled arbitrarily, including during transient times. It has become. FIG. 5 shows a control flow in automatic transmission computer C. First, in steps 202 to 206, the output shaft rotation speed N O of the automatic transmission and the opening degree θ1 of the first throttle valve 28 are determined.
, the opening degree θ2 of the second throttle valve 32 are read, respectively. In step 208, the equivalent throttle opening degree θ is calculated using the above-mentioned calculation formula. F in step 210 is a flag for flow control. Initially, it is set to zero, so step 212
Then, a gear change judgment is made based on the output shaft rotational speed NO and the throttle opening θ1 of the first throttle valve 28. Here, the opening degree θ2 of the second throttle valve 32 is determined by detecting the amount of slip of the drive wheels 5-16=〇152, and then determining the opening degree θ2 of the second throttle valve 32. Since it is used to control the engine output so that it converges, it may open and close in short cycles, and therefore,
The opening degree θ2 of this second throttle valve 32 or this θ
This is because if the shift judgment is made using the equivalent throttle opening θ taken into account in 2, there is a risk that the shift will be performed frequently. If there is a shift determination in step 212, a shift output is performed in step 214, and in step 216, the equivalent throttle opening θ, the selection position of the pattern select switch (economy driving E pattern and power driving P pattern), and the speed change are determined. Depending on the type, the electromagnetic proportional valve So
Determine the load current Ip to. Then step 220
．． 224, the load current 1p determined in step 216 is output until a certain period of time Ts (the time considered to end the gear shift) has elapsed, and after that, the 7 lag F is set to zero, and the load current determined in step 218 is output. Step 226) to change and output the current Ip. On the other hand, if it is determined in step 212 that there is no gear shift, the process proceeds to step 218 to adjust the equivalent throttle opening θ.
, the load current Ip is determined according to the output shaft rotational speed NON and the gear position at that time, and the process proceeds to step 226. Note that steps 216 and 2 are shown in FIGS. 6 and 7.
An example of a map used when determining the load current IP in No. 18 is shown. In both figures, the unit of load current Ip is ampere. In addition, in the above embodiment, an example was shown in which the second throttle valve was provided for the purpose of controlling the slip of the vehicle, but in the present case 1 and the second invention, the purpose of providing the second throttle valve was is not limited. Also, the second, third...
・The number of throttle valves is also not limited. In the first invention, there is no limitation as to whether the second, third, etc. throttle valves are arranged in parallel or in series. In addition, in the above embodiment, when controlling the hydraulic pressure in the hydraulic control device, the equivalent opening θ of the first throttle valve opening θ1 and the opening θ2 of the second throttle valve is determined by calculation, and this equivalent opening θ is calculated. The oil pressure was determined based on the opening degree θ, but (first invention), when the first throttle valve and the second throttle valve are arranged in series, generally the throttle Since the engine output is controlled by the throttle valve with the smaller opening degree, the magnitudes of θ1 and θ62 may be compared and hydraulic control may be performed depending on the smaller one of them (second invention). By doing so, the initial objective of the present invention can be substantially achieved without performing complicated equivalent opening degree calculations.

【Effect of the invention】

As explained above, according to the present invention, even if there are multiple throttle valves, the control hydraulic pressure in the hydraulic control device of the automatic transmission can be regulated to a hydraulic pressure commensurate with the actual engine output, and the gear shift The excellent effects of being able to control the speed change of an automatic transmission using hydraulic pressure with small shock, low power loss in the pump, and sufficient durability of the frictional engagement device can be obtained. .

[Brief explanation of drawings]

1A and 1B are block diagrams showing the main points of the bookcase 1 and the second invention, respectively, and FIG. 2 is a slip control to which the hydraulic control device for an automatic transmission according to the present invention is applied. A schematic configuration diagram showing the engine surroundings, automatic transmission, and wheel portion of a vehicle in which the device is installed, FIG. 3 is a block diagram showing the input/output relationship in the above embodiment device, and FIG. 4 is a diagram showing the same automatic transmission. FIG. 5 is a flowchart showing the control routine in the automatic transmission computer, and FIGS. 6 and 7 are examples of maps used to determine the load current 1p in the same routine. FIG. A... Traction computer, B... Engine computer, C... Automatic transmission computer, D... Hydraulic control device, So... Electromagnetic proportional valve, 28... First throttle valve, 32. ...Second throttle valve, 58...Automatic transmission.

Claims (8)

[Claims] (1) In a hydraulic control system for an automatic transmission used in combination with an engine having at least two throttle valves, means for determining an equivalent throttle opening for the engine from the opening of each throttle valve; 1. A hydraulic control device for an automatic transmission, comprising: means for adjusting the control hydraulic pressure in the hydraulic control device depending on the pressure. (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 frictional 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 disposed within the hydraulic control device. (6) The hydraulic control device for an automatic transmission according to any one of claims 1 to 5, wherein the pressure regulating means uses an electromagnetic proportional valve. (7) The hydraulic control device for an automatic transmission according to any one of claims 1 to 5, wherein the pressure regulating means uses a duty valve. (8) In a hydraulic control device for an automatic transmission used in combination with an engine having at least two throttle valves arranged in series, means for determining the throttle valve in the lowest opening state, and the opening degree. 1. A hydraulic control device for an automatic transmission, comprising: means for adjusting the control hydraulic pressure within the hydraulic control device depending on the opening degree of a throttle valve that is lowest.