JPH1151166A - Controller of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the worsening of a gear change shock and to obtain good gear change feeling by using a target rotation number as a target value for control and actual rotation number detected by a rotation detection means as a feedback value and sending commands to a liquid pressure adjusting means to feedback-control liquid pressure. SOLUTION: An input shaft rotation sensor 1 detects the rotation number of an input shaft of a gear change mechanism in an automatic transmission. A control unit 2 constitutes a memory means and a control means, operates in accordance with a program set in advance, consists of a microcomputer provided with a memory which stores various set values, and controls oil pressure on a tightening side in an inertia phase during gear change. A line pressure adjusting means 3 operates based on an oil pressure control signal of the control unit 2 and adjusts line pressure and oil pressure of the gear change mechanism. A throttle opening degree sensor 4 detects a degree of opening of a throttle valve of a vehicle. An engine load sensor 5 detects engine load of the vehicle. Consequently, almost ideal gear change feeling as designed is obtained design.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for controlling a shift of a hydraulic pressure supplied to a fastening element of a speed change mechanism in an automatic transmission. The present invention relates to a control device for an automatic transmission that can realize the above.

[0002]

2. Description of the Related Art Generally, as an automatic transmission for a vehicle,
2. Description of the Related Art It has become widespread to input the rotation of an engine via a torque converter, change the speed by a transmission mechanism having a plurality of planetary gear sets, and output the speed to a propeller shaft (axle side). A transmission mechanism in this type of automatic transmission transmits the rotation of the input shaft from the torque converter to a specific gear or carrier that constitutes a planetary gear according to the shift position, or controls the rotation of the specific gear or carrier. To transmit power to the output shaft as appropriate, or to restrict the rotation of a specific gear or carrier as appropriate,
Usually, a plurality of hydraulic fastening means such as clutches and brakes are provided.

[0003] By controlling a solenoid valve or the like incorporated in the hydraulic control circuit, the above-mentioned fastening means is fastened or released to effect a gear shift. In this case, when the fastening means switches from disengagement to engagement or from engagement to disengagement, if the change in the fastening force does not progress appropriately, there is a problem that an excessive torque shock occurs. For example, in a shift-up operation, in a stage (so-called inertia phase) after the time point at which the first stage of shifting (so-called torque phase) ends when the load on the disengagement side fastening means decreases to zero and the actual gear ratio starts to change. By appropriately increasing the fastening capacity of the fastening means on the fastening side (that is, the maximum transmission torque corresponding to the supplied oil pressure) at an increasing rate corresponding to the throttle opening and the like, the rotational speed of the input shaft of the transmission mechanism is appropriately changed. Needs to be changed.

In this case, if the engagement capacity is too large, the rotation speed rapidly decreases and the shift time required for upshifting is shortened, but the output shaft torque temporarily increases and a large shift shock occurs. Occurs. On the other hand, if the engagement capacity is too small, the shift time becomes too long, resulting in a crisp shift feeling. Therefore, various control techniques for controlling the hydraulic pressure at the time of shifting supplied to the fastening means to more ideally change the rotation speed of the input shaft of the transmission mechanism have been proposed.

For example, the control technique disclosed in Japanese Patent Application Laid-Open No. 1-1199050 is set in advance in accordance with the amount of change in the number of revolutions of the input shaft before and after the shift and the throttle opening in the inertia phase during the shift. The target rotation speed change rate of the input shaft is obtained based on the shift time and the target rotation speed of the input shaft is calculated for each control cycle from the target rotation speed change rate, and the target rotation speed is controlled. The present invention is characterized in that the supply hydraulic pressure is controlled in real time as a target value and the detected value of the rotation speed of the input shaft is used as a feedback value.

[0006]

However, in the conventional control technology disclosed in the above-mentioned publications, the target rotational speed of the input shaft, which is a reference for the hydraulic control during the shift, is determined by the rotational speed of the input shaft before and after the shift. Is calculated secondarily on the basis of the set value of the change amount or the set value of the shift time for each throttle opening. For this reason, there is a possibility that the target rotational speed may be different from an ideal value, and there is a problem that the speed change shock may be worse than expected at the time of design.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a control device for an automatic transmission in which deterioration of the shift shock is suppressed and a better shift feeling is obtained.

[0008]

According to a first aspect of the present invention, there is provided a control apparatus for an automatic transmission, comprising: a hydraulically driven coupling means for switching a coupling state of a rotation transmitting element of a transmission mechanism. An automatic transmission having a control device for controlling a hydraulic pressure supplied to the fastening means during a gear shift, wherein the hydraulic pressure adjusting means adjusts the hydraulic pressure based on a control signal, and an input shaft of the transmission mechanism. Rotation detection means for detecting the rotation speed, load detection means for detecting the throttle opening of the vehicle or the engine load, and the target rotation speed of the input shaft for each control cycle at the time of gear shifting is determined by the throttle opening of the vehicle or the engine. In accordance with a storage means stored in advance for each load, and a throttle opening or an engine load detected by the load detection means, a corresponding target rotational speed is sequentially read from the storage means. Control means for sending a control command to the hydraulic pressure adjusting means as a feedback target value of the actual rotational speed detected by the rotation detection means as a control target value, and controlling the hydraulic pressure in a feedback manner. It is characterized by having.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. First Example First, a first example will be described. As shown in FIG. 1, the control device of the present embodiment includes an input shaft rotation sensor 1, a control unit 2, a line pressure adjusting means 3, and a throttle opening sensor 4. Here, the input shaft rotation sensor 1
The sensor corresponds to the rotation detecting means of the present invention, and detects the rotation speed of the input shaft of the transmission mechanism in the automatic transmission, specifically, for example, the rotation speed of the rotation shaft connected to the turbine runner of the torque converter.

The control unit 2 constitutes storage means and control means of the present invention, and specifically operates according to a preset program.
The microcomputer is provided with a memory for storing various setting values. In this case, the control unit 2 is characterized in that it controls the hydraulic pressure of the engagement means on the engagement side in the inertia phase during shifting by the processing shown in the flowchart of FIG.

The line pressure adjusting means 3 is the hydraulic pressure adjusting means of the present invention. More specifically, the line pressure adjusting means 3 adjusts a duty solenoid valve or the like incorporated in a hydraulic control circuit normally provided at a lower portion of a transmission mechanism casing. The pressure means operates in accordance with a hydraulic pressure control signal of the control unit 2 to adjust a line pressure, which is an output pressure of an oil pump (not shown), to adjust a hydraulic pressure supplied to a fastening means of the transmission mechanism.

The throttle opening sensor 4 is a sensor for detecting the throttle opening of the vehicle, and corresponds to the load detecting means of the present invention. As the load detecting means, an engine load sensor 5 for detecting an engine load of the vehicle may be provided as shown by a dashed line in FIG. The engine load sensor 5 is a sensor that detects a value that can detect an engine load such as an intake pressure of the engine and a fuel injection amount.

The control of the hydraulic pressure of the disengagement side engaging means during gear shifting or the control of the hydraulic pressure on the engagement side in the torque phase may be performed by, for example, the control unit 2 in the conventional manner. Since the present invention is applied to the hydraulic control on the engagement side in the inertia phase, the description of the other hydraulic control processing is omitted. In addition, the configuration and operation of the transmission main body such as the specific configuration of the transmission mechanism are not particularly limited, and the description thereof will be omitted.

Next, the hydraulic control process of the fastening means on the fastening side in the inertia phase during gear shifting by the control unit 2 will be described with reference to the flowchart of FIG. This process is executed starting from the detection of the inertia phase during shifting. Here, the inertia phase detection is performed based on, for example, the following principle by detecting the start of the inertia phase which is the second stage of the shift. That is,
At the start of the inertia phase, the input shaft rotation sensor 1
If the number of rotations of the transmission input shaft detected by (1) is an upshift, it starts to decrease sharply. Therefore, it is determined that the inertia phase has started when such an inflection point of the change in the rotational speed is detected.

Then, when the processing is started as described above,
First, in step S2, a throttle opening change amount ΔTH during a shift time is obtained based on, for example, a detection value from the throttle opening sensor 4, and then in step S4, the throttle opening change amount ΔTH and a preset throttle position are set. The opening change amount ΔTH ₀ is compared. Then, ΔTH ≧ ΔTH ₀
If you stop this control, if .DELTA.TH <.DELTA.TH _0, the process proceeds to step S6.

Next, in step S6, the actually measured value Ni of the rotation speed detected by the input shaft rotation sensor 1 is read, and then in step S8, the stored ideal target rotation speed Nn of the input shaft is read. Here, the target rotation speed Nn is read from a data table as shown in FIG. 4A stored in a ROM or the like in the control unit 2, for example.

A plurality of data tables are registered in advance for each shift stage, vehicle speed, and each control cycle at the time of shifting, and the control unit 2 corresponds to the shift stage, the vehicle speed at that time, and the control cycle. First, a process of selecting a data table is performed. Then, from the selected data table, the target rotation speed corresponding to the throttle opening detected by the throttle opening sensor 4 at that time is read as the target rotation speed Nn.

The data table of the target rotation speed may be a table in which the target rotation speed is set for each predetermined range of the throttle opening as shown in FIG. Also,
A data table in which a target rotation speed is set for each engine load as shown in FIG. 13C may be set, and the target rotation speed data may be selected based on the engine load instead of the throttle opening.

Next, in step S10, step S6
A deviation e (e = Ni−Nn) for feedback control is obtained from the actually measured value Ni of the rotation speed read in step S8 and the target rotation speed Nn read in step S8.

Next, in step S12, step S
A hydraulic control signal for making the deviation e obtained at 10 close to zero is output to the line pressure adjusting means 3. Finally, in step S14, it is determined whether or not the inertia phase has been completed. If the inertia phase has been completed, the present process ends, and if not, the process returns to step S2 and repeats the present process at a predetermined cycle. The determination as to whether or not the inertia phase has been completed is made based on, for example, the following principle. That is, in the case of the upshift, the reduction of the rotation speed Ni detected by the input shaft rotation sensor 1 stops at the end of the inertia phase. Therefore, when such an inflection point of the change in the rotational speed is detected, it is determined that the inertia phase has ended.

[0021] In the control process, unless the .DELTA.TH ≧ .DELTA.TH _0, until the inertia phase ends, repeats the processing in step S6~S12 is, the rotational speed measured value Ni and the target rotational speed Nn to be read anew each time , And a control oil pressure signal based on the deviation e thus calculated is output every cycle.

In the control device of the present embodiment described above, FIG.
In the form of a data table as exemplified in (a), the target rotation speed of the input shaft at the time of gear shifting is stored in advance, and among those, the one that is optimal for the throttle opening or engine load at that time is stored. It is read and used as a target value for the hydraulic feedback control of the fastening means at the time of shifting. Therefore, as compared with the conventional configuration in which the target rotation speed is secondarily obtained, the value of the target rotation speed can be more reliably set to the ideal value, and the processing speed can be remarkably increased. Thus, it is possible to control the input shaft rotation speed at the time of gear shifting, and to obtain a gear shift feeling closer to the ideal as designed.

Second Example Next, a second example will be described. The control device of the present example is characterized in that the control unit 2 controls the hydraulic pressure of the fastening means on the fastening side in the inertia phase during the gear shift,
The other configuration is the same as that of the first example, and a duplicate description will be omitted. Hereinafter, the control processing of the control unit 2 will be described with reference to FIG.

When the process is started with the detection of the inertia phase during the shift as a starting point, first, in step S22, the value of the first FLAG indicating whether or not it is the first control cycle immediately after the start of the process is set to "1". Next, step S24
Then, for example, a throttle opening change amount ΔTH during a shift time is obtained based on a detection value from the throttle opening sensor 4, and then, in step S26, the throttle opening change amount ΔTH and a preset throttle opening change Quantity ΔT
Compare H ₀ . If ΔTH ≧ ΔTH ₀ , the control is stopped, and if ΔTH <ΔTH ₀ , the process proceeds to step S
Proceed to 28.

Next, in step S28, the actually measured value Ni of the rotation speed detected by the input shaft rotation sensor 1 is read. Then, in step S30, the value of the first FLAG is determined. , "1", the process proceeds to step S36. Then, in step S32, the actual measured value Ni of the rotation speed read in step S28 is registered in the memory as an initial value. Next, in step S34, the value of the initial FLAG is updated to "0",
Return to 24.

On the other hand, in step S36, the detection value of the throttle opening sensor 4 or the engine load sensor 5 is read, and in step S38, the stored ideal change rate of the rotation speed Nt of the input shaft (that is, the gradient) is read. ). Here, the rate of change of the rotation speed Nt is read from a data table as shown in FIG. 4D stored in a ROM or the like in the control unit 2, for example. A plurality of data tables are registered in advance for each shift speed, and the control unit 2 first performs a process of selecting a corresponding data table according to the shift speed. Then, from the selected data table, the change rate of the rotation speed Nt according to the detection value of the engine load sensor 5 and the like which is being read at that time is read.

Next, in step S40, step S38
The change rate of the rotation speed Nt read in step S32
From the initial value of the input shaft speed registered in
Ask for. Next, in step S42, step S28
The actual measured value Ni of the number of revolutions read in step S40
A deviation e (e = Ni−Nn) for feedback control is obtained from the target rotation speed Nn calculated in the above.

Next, in step S44, step S
A hydraulic control signal for making the deviation e obtained at 42 close to zero is output to the line pressure adjusting means 3. Finally, in step S46, it is determined whether or not the inertia phase has been completed. If the inertia phase has been completed, the present process ends. If not, the process returns to step S24 and repeats the present process at a predetermined cycle.

In the above control processing, the processing of step S32 is executed only in the first cycle immediately after the start of the inertia phase by the branch processing of step S30 and the update processing of the first FLAG of step S34. The rotation speed Ni is set as an initial value. And then, as long as it does not become ΔTH ≧ ΔTH _0, until the inertia phase is completed, the step S28, S36~
The process of S44 is repeated, and the deviation e is calculated from the initial value (constant value) of the rotation speed, the actual measurement value Ni of the rotation speed newly read every time, and the rate of change of the rotation speed, and is thus sequentially calculated. A control oil pressure signal based on the deviation e is output every cycle.

According to the control device of the present embodiment described above, the target change rate itself during the speed change of the rotation speed of the input shaft is stored in advance in the form of a data table as illustrated in FIG. Of these, the optimal one for the throttle opening or the engine load at that time is read out, and the target rotational speed calculated from the target change rate is used as the target value of the hydraulic feedback control of the fastening means during shifting. Is done. For this reason, as in the conventional case, the rate of change of the input shaft speed is determined based on the change amount of the speed of the input shaft before and after the speed change and a preset shift time, and further, each control cycle is determined from the change rate. Compared to the configuration that calculates the target rotation speed of each input shaft, the value of the target rotation speed can be more reliably set to the ideal value and the processing speed can be increased. The number can be controlled, and a more ideal shift feeling as designed can be obtained.

[0031]

According to the control device for an automatic transmission according to the first aspect, the target rotation speed itself at the time of shifting the input shaft is stored in the storage means in advance, of which the throttle opening or the engine at that time is stored. The optimum value for the load is read out by the control means and used as the target value of the hydraulic feedback control of the fastening means at the time of shifting. Therefore, as compared with the conventional configuration in which the target rotation speed is secondarily obtained, the value of the target rotation speed can be more reliably set to the ideal value, and the processing speed can be remarkably increased. Thus, it is possible to control the input shaft rotation speed at the time of gear shifting, and to obtain a gear shift feeling closer to the ideal as designed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a control device that is a first example of the present invention.

FIG. 2 is a flowchart showing a characteristic control process of the apparatus.

FIG. 3 is a flowchart illustrating a characteristic control process of a control device according to a second example of the present invention.

FIG. 4 is a diagram showing a configuration example of a data table stored in a storage unit of the present invention.

[Explanation of symbols]

 Reference Signs List 1 input shaft rotation sensor (rotation detection means) 2 control unit (storage means, control means) 3 line pressure adjustment means (hydraulic pressure adjustment means) 4 throttle opening sensor (load detection means) 5 engine load sensor (load detection means) Nt Input shaft speed Nn Target speed Ni Actual speed

Claims (1)

[Claims] In an automatic transmission having a hydraulically driven coupling means as a means for switching a coupling state of a rotation transmitting element of a transmission mechanism, the control device controls a hydraulic pressure supplied to the coupling means at the time of shifting. A hydraulic pressure adjusting means for adjusting the hydraulic pressure based on a control signal; a rotation detecting means for detecting a rotation speed of an input shaft of the transmission mechanism; and a load detecting means for detecting a throttle opening of the vehicle or an engine load. A storage means in which the target rotation speed of the input shaft for each control cycle at the time of shifting is stored in advance for each throttle opening or engine load of the vehicle; and a throttle opening or engine detected by the load detecting means. In accordance with the load, the corresponding target rotational speed is sequentially read from the storage means, and the read target rotational speed is used as a control target value, and the actual target speed detected by the rotation detecting means is detected. Control apparatus for an automatic transmission for a control unit for the liquid feedback the pressure sends a control command to pressure adjusting means controlling the rotational speed as the feedback value comprising the.