JP3232165B2 - Line pressure control device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line pressure control device for an automatic transmission.

[0002]

2. Description of the Related Art A conventional line pressure control device for an automatic transmission is disclosed in Japanese Patent Application Laid-Open No. 3-249466. The line pressure control device of the automatic transmission shown therein sets the line pressure based on the intake air amount, but detects a change in engine speed and a shift detecting means for detecting that a shift is being performed. Based on the detection result of the rotation change detecting means, the amount of intake air for setting the line pressure by the line pressure setting means is fixed to the detected value at the time of the occurrence of the rotation change from the occurrence of the rotation change during the gear change to the end. . This is to prevent the intake air amount from fluctuating greatly during gear shifting, thereby preventing a change in line pressure and a change in gear shifting performance.

[0003]

However, in the above-described conventional line pressure control apparatus for an automatic transmission, the amount of intake air from the occurrence of a rotation change during a gear shift to the end thereof is fixed to a detection value at the time of the rotation change. However, when the engine load changes during gear shifting, there is a problem that the line pressure becomes insufficient or becomes too large. The present invention is to solve such a problem.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by changing the amount of intake air in accordance with the amount of change in engine load. That is, the line pressure control device for an automatic transmission according to the present invention includes an intake air amount detecting means for detecting an intake air amount per unit rotation speed of the engine, and a line for setting a line pressure based on the detected intake air amount. Pressure setting means, line pressure control means for controlling a line pressure of the automatic transmission by driving a line pressure actuator based on the set line pressure, shift detection means for detecting that a shift is being performed, and engine rotation Rotational change detection means for detecting a change in speed, and intake air amount fixing for fixing the intake air amount for setting line pressure to a detection value at the time of rotation change occurrence based on the detection results of the shift detection means and the rotation change detection means. Means for changing the intake air amount according to the change amount when the change amount of the engine load detected by the engine load detection means during the shift is equal to or more than a predetermined value. Having a gas amount changing means, characterized in that. The engine load may be determined based on the intake air amount of the engine. Further, the engine load may be determined based on an opening area of a throttle valve of the engine. Further, a line pressure control device for an automatic transmission according to the present invention includes a fuel injection amount detection unit that detects a fuel injection amount of an engine, a line pressure setting unit that sets a line pressure based on the detected fuel injection amount, Line pressure control means for controlling a line pressure of an automatic transmission by driving a line pressure actuator based on a set line pressure, shift detection means for detecting that a shift is being performed, and detecting a change in engine speed. Rotation change detection means, and a fuel injection amount fixing means for fixing the fuel injection amount for line pressure setting to a detection value at the time of rotation change occurrence, based on the detection results of the shift detection means and the rotation change detection means,
A fuel injection amount changing unit that changes the fuel injection amount according to the change amount when the change amount of the engine load detected by the engine load detection unit during the shift is equal to or more than a predetermined value. And The engine load may be determined based on the intake air amount of the engine. Further, the engine load may be determined based on an opening area of a throttle valve of the engine.

[0005]

The intake air amount for line pressure setting is detected by the intake air amount fixing means by the intake air amount detecting means by the intake air amount fixing means based on the detection result of the shift detecting means and the engine speed detected by the rotation change detecting means when the rotation change occurs. Fixed value. When the change amount of the engine load becomes equal to or more than the predetermined value during the shift, the intake air amount is changed by the intake air amount changing means, and the line pressure is reset based on the changed intake air amount by the line pressure setting means. As a result, even if the engine load changes during gear shifting, the line pressure does not become excessive or insufficient.

[0006]

FIG. 2 shows an embodiment of the present invention. An automatic transmission 12 is provided on the output side of the engine 10. The automatic transmission 12 includes a torque converter 14 located on the output side of the engine 10, a gear transmission 16 connected via the torque converter 14, and various transmission elements (not shown) in the gear transmission 16. And a hydraulic actuator 18 for performing a connecting and releasing operation. The operating oil pressure for automatic shifting of the hydraulic actuator 18 is controlled on / off via electromagnetic valves 20 and 22. Automatic transmission 12
An output shaft 24 is led out from the end opposite to the side where the torque converter 14 is attached. An oil pump 26 driven by an input shaft of a gear transmission is used to obtain a line pressure which is an operating oil pressure for the torque converter 14 and the hydraulic actuator 18, and an orifice 28, an electromagnetic valve 30 (line pressure actuator),
A pressure modifier valve 32 and a pressure regulator valve 34 are provided. Electromagnetic valve 3
0 is duty-controlled as described later, and the orifice 2
8 based on the discharge pressure of the oil pump 26 guided through
Obtain pilot pressure. The pressure modifier valve 32 amplifies the pilot pressure. The pressure regulator valve 34 regulates the discharge pressure from the oil pump 26 to a line pressure proportional to the pilot pressure from the pressure modifier valve 32, and
And a hydraulic circuit such as a hydraulic actuator 18. The engine 10 includes a hot wire type aero flow meter 38 for detecting an intake air flow rate Q in an intake system thereof, a crank angle sensor 40 on a crankshaft or a shaft rotating in synchronization with the crankshaft, and a throttle valve 42 of the intake system. A potentiometer type throttle opening sensor 44 for detecting the opening TVO is provided. The signal of the crank angle sensor 40 is, for example, a pulse signal for each reference crank angle, and the engine speed N is calculated from the cycle thereof. Signals from the aero flow meter 38, the crank angle sensor 40, and the throttle opening sensor 44 are input to the control unit 36. The control unit 36 has a vehicle speed sensor 46 for detecting a vehicle speed VSP by obtaining a rotation signal from the output shaft 24 of the automatic transmission 12.
Is also input. The control unit 36 has a built-in microcomputer and mainly performs shift control and line pressure control. The shift control is performed in accordance with the operating position of the select lever. In particular, when the select lever is in the D range, the shift control is performed according to the throttle opening TVO and the vehicle speed VSP.
The shift positions of the first to fourth speeds are automatically set, and the combination of on / off of the electromagnetic valves 20 and 22 is controlled to control the gear type transmission 16 via the hydraulic actuator 18 to the shift position. The line pressure control is performed by duty control of the electromagnetic valve 30 which is a line pressure actuator according to a line pressure control routine shown in FIG. Here, the line pressure can be increased by increasing the duty (valve opening time ratio).

Next, the line pressure control will be described according to the control flow shown in FIG. First, the intake air amount Q detected by the aero flow meter 38, the engine speed N calculated based on the signal from the crank angle sensor 40, and the throttle opening θ detected by the throttle opening sensor 44
Is read (step 100). Next, it is determined whether or not the shift is being performed (the same 102). If the shift is in progress, it is determined whether the amount of change ΔN of N with respect to the previous value is equal to or greater than a predetermined value (104). If ΔN is equal to or greater than the predetermined value, it is determined whether the change amount Δθ of θ with respect to the previous value is equal to or greater than the predetermined value (106). If Δθ is equal to or larger than the predetermined value, C is set from the previously set relationship between Δθ and the correction amount C shown in FIG. 4 (108). Next, a torque TQ = K · (C · Q) / N is calculated from Q, N, and C as corresponding to the intake air amount per unit rotation speed (110). Here, K is a constant. Next, a PL is set in accordance with the calculated TQ from the previously set relationship between the TQ and the PL at the time of the shift (11).
2). Next, the duty corresponding to the set PL is output (114). As a result, the electromagnetic valve 30 is driven to obtain an optimal line pressure. In step 104, if ΔN is smaller than the predetermined value, TQ = K · Q
/ N is calculated (id 116). Next, step 112
And 114 are performed. As a result, the electromagnetic valve 30 is driven to obtain an optimal line pressure. If Δθ is smaller than the predetermined value in step 106, the calculation of TQ based on the latest Q and N is not performed, and step 112 is executed based on the value of TQ at the time when the rotation change occurs. 114 is performed. As a result, the electromagnetic valve 30 is driven to obtain an optimal line pressure. If it is determined in step 102 that the gear is not being shifted, a PL is set in accordance with the value of TQ at the time of rotation change from the previously set relationship between the normal TQ and the line pressure PL (122). As a result, the electromagnetic valve 30 is driven to obtain an optimal line pressure. Step 100,
110 and 120 constitute intake air amount detecting means, step 102 constitutes shift detecting means, step 104 constitutes rotation change detecting means, step 106 constitutes engine load detecting means, and step 108 constitutes intake air amount detecting means. Steps 112 and 122 constitute the line pressure setting means, Step 114 constitutes the line pressure control means, and Step 10
The portion that does not execute step 4 and the portion that does not execute step 108 in the determination of step 106 constitute intake air amount fixing means.

In the above-described embodiment, the line pressure is changed by obtaining TQ from Q and N. However, since TQ is equivalent to the basic fuel injection amount which is the basis for calculating the fuel injection amount by the electronically controlled fuel injection device. Thus, the line pressure can be changed.

[0009]

According to the present invention, the line pressure is reset by changing the intake air amount according to the change amount of the engine load during shifting. As a result, even if the engine load changes during gear shifting, the line pressure does not become excessive or insufficient.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between components of the present invention.

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

FIG. 3 is a control flow of line pressure control.

FIG. 4 is a diagram showing a relationship between a change amount of a throttle opening and a correction amount.

[Explanation of symbols]

 Reference Signs List 10 engine 12 automatic transmission 30 solenoid valve 38 aero flow meter 40 crank angle sensor 44 throttle opening sensor

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ identification code FI F16H 59:74 F16H 59:74 (58) Investigated field (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (6)

(57) [Claims] 1. An intake air amount detecting means for detecting an intake air amount per unit rotation speed of an engine; a line pressure setting means for setting a line pressure based on the detected intake air amount; Line pressure control means for controlling a line pressure of an automatic transmission by driving a line pressure actuator based on the speed, shift detection means for detecting that a shift is being performed, and rotation change detection means for detecting a change in engine rotation speed And an intake air amount fixing means for fixing an intake air amount for setting line pressure to a detection value at the time of occurrence of a rotation change based on the detection results of the speed change detection means and the rotation change detection means. In the pressure control device, when the amount of change in the engine load detected by the engine load detecting means during the shift is equal to or greater than a predetermined value, the amount of intake air is changed according to the amount of change. Having a step, the line pressure control device for an automatic transmission, characterized in that. 2. The automatic transmission line pressure control device according to claim 1, wherein the engine load is determined based on an intake air amount of the engine. 3. The line pressure control device for an automatic transmission according to claim 1, wherein the engine load is determined based on an opening area of a throttle valve of the engine. 4. A fuel injection amount detecting means for detecting a fuel injection amount of an engine, a line pressure setting means for setting a line pressure based on the detected fuel injection amount, and a line pressure based on the set line pressure. Line pressure control means for controlling the line pressure of the automatic transmission by driving an actuator; shift detection means for detecting that a shift is being performed; rotation change detection means for detecting a change in engine rotation speed; and shift detection means And a fuel injection amount fixing means for fixing the fuel injection amount for setting the line pressure to a detection value at the time of occurrence of the rotation change, based on the detection result of the rotation change detection means, and a line pressure control device for an automatic transmission, comprising: When the change amount of the engine load detected by the engine load detection means during the shift is equal to or more than a predetermined value, the fuel injection amount changing means changes the fuel injection amount according to the change amount. Doo line pressure control device for the automatic transmission according to claim. 5. The line pressure control device for an automatic transmission according to claim 4, wherein the engine load is determined based on an intake air amount of the engine. 6. The line pressure control device for an automatic transmission according to claim 4, wherein the engine load is determined based on an opening area of a throttle valve of the engine.