JP3396098B2 - Traveling state detection device, automatic transmission control device, and engine control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting a running condition of a vehicle, and more particularly, to a running condition detecting device for detecting whether a running place is a lowland or a highland, and a control relating to shifting according to the running state. The present invention relates to a control device for an automatic transmission that performs, and a control device for an engine that controls driving of an engine according to a traveling state.

[0002]

2. Description of the Related Art Generally, in an automatic transmission, a shift point is set based on a relationship between a vehicle speed and a throttle opening corresponding to an output torque of an engine.
The optimum shift point is set according to the engine characteristics.
However, this engine characteristic is a characteristic in a lowland, and when the vehicle travels in a highland, the output torque of the engine is reduced due to the reduction of the air density, and the engine speed-engine output torque characteristic changes.

Therefore, when the high altitude traveling state is detected,
It is considered that the shift control of the automatic transmission is changed to control according to the reduction of the output torque of the engine. An apparatus for performing such control is, for example, Japanese Patent Application Laid-Open No. 3-1894.
There is known a shift control device for an automatic transmission described in Japanese Patent Publication No. 59, in which the conventional device outputs an actual engine output according to an air density detection means of engine intake air and a detected density state of intake air. And a shift control means for performing shift control with a shift pattern corrected to correspond to.

Therefore, when the high-altitude running state is detected by the air density detecting means due to the decrease of the intake air density, the shift point is changed to perform the shift control in response to the decrease of the output torque of the engine due to the decrease of the intake air density. What you do,
As a result, the shift control performance is improved.

[0005]

However, the above-mentioned conventional techniques have the problems listed below.

Driving state of engine (high-altitude running state)
When detecting the, the engine is configured to be estimated from the intake air density of the engine.
Since not only the intake air density but also factors such as air fuel consumption are related, the accuracy is low only by detecting the intake air density of the engine.

In an automatic transmission control device in which the control contents of the automatic transmission are switched according to the running state (intake air density), it is necessary to attach an intake air density detection means to the engine, Since the product cannot be completed on the automatic transmission side, the work of connecting with the engine side is required at the time of assembling to the vehicle body, and the assembling work increases.

As described above, the shift control on the automatic transmission side is performed in order to perform the shift corresponding to the engine torque even if the driving state of the engine changes due to the change of the running state in the lowlands and the highlands. Even if it does not exist, a new means for achieving a shift corresponding to the engine torque is also desired.

The present invention has been made by paying attention to the above-mentioned conventional problems, and improves the detection accuracy of a running state in lowlands and highlands, and the running state can be detected only by the automatic transmission side. In addition, the purpose of the present invention is to eliminate the need to switch the control on the automatic transmission side when performing a gear shift corresponding to the engine torque in response to a change in running conditions in the lowlands and highlands on the engine side. .

[0010]

In order to achieve the above object, as shown in the claim correspondence diagram of FIG. 1 (a), in the invention of claim 1, the turbine of the torque converter TC of the automatic transmission AT is disclosed. Turbine rotation speed detection means a for detecting the rotation speed, engine rotation speed detection means b for detecting the engine rotation speed of the engine E that transmits torque to the automatic transmission AT, and capacity characteristics of the torque converter TC with respect to the speed ratio. , And a storage means c in which the engine torque characteristic with respect to the engine rotation speed is stored, and a speed ratio of the torque converter TC is obtained based on the detected engine speed and turbine speed, and the speed ratio and the capacity characteristic are obtained. While calculating the actual torque based on the actual torque, the estimated torque is obtained from the engine speed and the engine torque characteristic. The difference between the estimated torque is determined to lowland traveling state is less than a predetermined value, also to constitute a traveling state detection device in the traveling state determining means d to determine that high altitude running state when it becomes more than a predetermined value.

According to the second aspect of the invention, the control device for the automatic transmission performs the shift control for lowland when the lowland traveling state is detected based on the detection of the traveling state detecting device d according to the first aspect. A shift control means e is provided for performing shift control for high altitudes when a high altitude traveling state is detected.

According to the third aspect of the present invention, the shift control means e is adapted to reduce the output torque of the engine E in the highland and the lowland map relating to at least one of the hydraulic pressure and the shift point according to the engine torque characteristic in the lowland. The shift control is performed based on the corresponding map for high altitude.

Further, in the invention according to the fourth aspect, the shift control means e is configured to perform the learning control according to the decrease in the output torque of the engine E in the highland when the highland running is detected.

Further, in the invention described in claim 5, the control device for the engine includes the traveling state detection device e according to claim 1.
An engine drive control means f is provided for performing drive control for high altitudes when detecting a high altitude traveling state based on the above detection.

According to the sixth aspect of the invention, the engine control unit is provided with an automatic transmission A as shown in FIG. 1 (b).
Turbine speed detecting means a for detecting the turbine speed of the torque converter TC of T, engine speed detecting means b for detecting the engine speed of the engine E transmitting torque to the automatic transmission AT, and the torque converter T
The storage means c in which the capacity characteristic with respect to the speed ratio of C and the engine torque characteristic with respect to the engine speed are stored, and the speed ratio of the torque converter TC is obtained based on the detected engine speed and turbine speed. A torque difference calculating means d2 for calculating an actual torque based on the speed ratio and the capacity characteristic, obtaining an estimated torque from the engine speed and the engine torque characteristic, and obtaining a difference between the actual torque and the estimated torque; The engine drive control means f2 for controlling the drive of the engine is provided so that the difference between the actual torque and the estimated torque becomes zero.

[0016]

When the vehicle is traveling, the traveling state judging means d inputs the turbine rotational speed from the turbine rotational speed detecting means a and the engine rotational speed from the engine rotational speed detecting means b, and the torque converter TC from both rotational speeds. Find the speed ratio of. Then, the actual torque is calculated from the calculated speed ratio based on the capacity characteristic with respect to the speed ratio of the torque converter TC stored in advance in the storage means c.

On the other hand, the storage means c stores the engine torque characteristic with respect to the engine speed in the lowland in advance, and the running state judging means d determines the engine speed in the lowland from the detected engine speed and the engine torque characteristic. Find the corresponding estimated torque.

Therefore, the engine E is used when traveling in the lowland.
Since the actual output torque of the above is a torque that substantially matches the engine torque characteristic known in advance, the running state determination means d causes the actual torque and the estimated torque to substantially match, and the difference between the two is smaller than a predetermined value. Since the value becomes a value, it is determined that the vehicle is running in a lowland. On the other hand, when traveling at high altitudes, the actual output torque of the engine E is lower than the engine torque characteristic, so that in the traveling state determination means d, the difference between the actual torque and the estimated torque becomes large and becomes a predetermined value or more. Judged as running in high altitude.

According to the second aspect of the present invention, when the traveling state judging means d detects the lowland traveling state, the shift control means e carries out the shift control for level ground, and the traveling state judging means d carries out the highland traveling state. When detecting, the shift control means e performs shift control for high altitudes.

In the apparatus according to the third aspect of the invention, when the running condition judging means d detects a lowland running condition, the shift control means e performs the shift control for level ground. At this time, the map of the hydraulic pressure for level ground is used. And / or the map of the shift points for the level ground are used. Further, when the traveling state judging means d detects a high-altitude traveling state, the shift control means e performs shift control for high altitudes. At this time, a map of hydraulic pressure for high altitudes and a map of shift points for high altitudes are displayed. Use one or both.

In the apparatus according to the fourth aspect, when the traveling state judging means d detects the lowland traveling state, the shift control means e performs the learning control for flatland, and the traveling state judging means d carries out the highland traveling state. While detecting, the shift control means e performs learning control for high altitudes.

According to the fifth aspect of the present invention, when the running condition judging means d detects a high altitude running condition, the engine drive control means f increases the engine advance angle, boost pressure, or fuel supply amount, for example. Drive control for high altitude is performed.

In the apparatus according to the sixth aspect, the difference between the actual torque and the estimated torque is obtained by the torque difference calculating means d2,
If there is a difference, the engine drive control means f2 controls the drive of the engine so that the difference becomes zero. Therefore, even if the intake air density of the engine E decreases and the output torque of the engine decreases due to traveling at high altitudes or the like, the output torque is increased by the drive control by the engine drive control means f2, and the engine torque characteristic in the lowlands is maintained. It Therefore, the automatic transmission to which the torque is transmitted from this engine can perform a shift corresponding to the torque even when the shift control similar to that in the lowland is performed in the highland.

[0024]

Embodiments of the present invention will be described with reference to the drawings. First, a first embodiment, which is an embodiment of the control device for an automatic transmission according to claim 3, will be described.

FIG. 2 is a schematic view showing the structure of the main part of the first embodiment device of the present invention. The torque converter 2a of the automatic transmission 2 to which the output torque is transmitted from the engine 1 and this torque converter 2a. Transmission mechanism 2 for changing a gear ratio between an input shaft 3 that is torque-transmitted via a vehicle and an output shaft 4 that is torque-transmittable to wheels.
b and are provided. In the figure, 2c is a drive plate, 2d is a turbine runner, 2e is a pump impeller, and 4a is a parking gear.

The speed change mechanism 2b has two planetary gear sets (not shown). The band servo BS, which serves as a frictional engagement element for coupling, separating, and stopping the rotating elements of the planetary gear set,
Reverse clutch R / C, high clutch H / C, forward clutch F / C, overrun clutch O / C, forward one-way clutch F / O ・ C, low one-way clutch L / O ・ C, low & reverse brake L & R /
B is provided, and each gear shift is performed by engaging and disengaging the friction engagement element as shown in the engagement operation diagram of FIG. 3 based on hydraulic control by a control valve (not shown). .

The operation of the control valve is performed by the AT control unit 6 shown in FIG. That is, the AT control unit 6 has an idle switch 7, a full throttle switch 8, a throttle sensor 9 and an engine rotation sensor 10 on the engine 1 side as input means, and an inhibitor switch 11 and an oil on the automatic transmission 2 side. It has a temperature sensor 12, a vehicle speed sensor 13, and a turbine sensor 14, determines a traveling state based on signals obtained from these, and shifts to an optimum gear ratio corresponding to the traveling state in the first shift. The solenoid 15, the second shift solenoid 16, the overrun clutch solenoid 17, the lock-up solenoid 18, and the line pressure solenoid 19 are driven to control the operation of the control valve to control the shift of the automatic transmission 2. There is. As shown in FIG. 2, the vehicle speed sensor 13 is a sensor that detects the rotation speed of the output shaft 4, and the turbine sensor 14 is the input that rotates integrally with the turbine runner 2d of the torque converter 2a. It is a sensor that detects the number of rotations of the shaft 3. Further, the AT control unit 6 is configured to exchange signals with an engine control unit 20 that controls driving of the engine 1.

By the way, the AT control unit 6 has a memory (not shown) in advance for gear shift control.
The shift control is performed based on the shift schedule and the line pressure characteristic stored in FIG. 5, and the shift schedules for the lowland (normal) shown in FIG.
In addition to the one for highlands shown in (b), the line pressure characteristic also has lowland (normal) and highlands as shown in FIG. The control is performed to detect whether the vehicle is in a running state and select a shift schedule and line pressure characteristic used for shift control according to the detection result. Below, regarding this control,
This will be described with reference to the flowchart of FIG. It should be noted that this flowchart is a subroutine for selecting a shift schedule and a line pressure characteristic, and shift control based on the selected shift schedule and line pressure characteristic is performed by a main routine (not shown). Further, in the shift schedule, as shown in the figure, the shift point for the highlands is set to the higher speed side than that for the lowlands,
The line pressure characteristics are set to a lower pressure for highlands than for lowlands.

In step S1, the engine speed n _e and the turbine speed n _p are read.

In step S2, the speed ratio of the torque converter is calculated by the following equation (1) based on the rotation speeds n _e and n _p read in step S1. Speed ratio = n _p / n _e (1) In step S3, a torque converter for a speed ratio (n _p / n _e ) previously stored in a memory (not shown) provided in the AT control unit 6 The capacity τ of the torque converter is obtained from the speed ratio obtained in step S2 based on the map showing the characteristics of the capacity τ (see FIG. 8).

In step S4, the actual engine torque T _e1 is calculated from the capacity τ of the torque converter and the engine speed n _e obtained in step S3 based on the following equation (2). Actual torque T _e1 = n _e ² × τ (2) In step S5, based on a map (see FIG. 9) showing the characteristics of the engine torque T _e with respect to the engine speed n _e stored in advance in the memory. , Engine speed n
_{From e} to estimated torque T on engine characteristics (in lowland)
_{Find e2} .

In step S6, the actual torque T _e1 is subtracted from the estimated torque T _e2 to calculate the torque difference T _e2-1 .

[0033] In step S7, the torque difference T _E2-1, it is determined whether more than a predetermined value A, YES i.e. torque difference T _E2-1 is, a large amount of torque reduction be more than the predetermined value A Therefore, if it is determined that the vehicle is traveling in the highland, the process proceeds to step S8. If NO, that is, the torque difference T _e2-1 is less than the predetermined value A and there is no torque reduction amount, the vehicle is traveling in the lowland. move on.

In step S8, FIG. 5 (b) and FIG.
The shift schedule and line pressure for highlands shown in are selected, and in step S9, the shift schedule and line pressure for lowlands shown in FIGS. 5A and 6 are selected.

Next, the operation of the first embodiment will be described.

(A) During lowland running During lowland running, the engine 1 has substantially the same characteristics as the engine torque T _e shown in FIG. Therefore, the torque difference T _e2-1 between the estimated torque T _e2 and the actual torque T _e1
Becomes less than the predetermined value A, and in the flowchart of FIG. 7, steps S1 → S2 → S3 → S4 → S5 → S6 → S.
The flow from 7 to S9 is followed, and the shift schedule and line pressure for lowlands are selected.

(B) During high altitude traveling During high altitude traveling, the output torque of the engine 1 decreases,
The characteristic of the engine torque T _e shown in FIG. 9 cannot be obtained.

Therefore, the actual torque T _e1 obtained from the engine speed n _e , the turbine speed n _p , and the prestored characteristic of the capacity τ in FIG. 8 decreases. Therefore, the torque difference T _e2-1 between the estimated torque T _e2 and the actual torque T _e1
When the actual torque T _e1 decreases until the torque becomes less than the predetermined value A, in the flowchart of FIG. 7, steps S1 → S
The sequence of 2 → S3 → S4 → S5 → S6 → S7 → S8 is followed, and the shift schedule and line pressure for high altitude are selected.

When the shift control is performed based on this high altitude shift schedule and line pressure characteristics, the line pressure with respect to the accelerator opening is reduced in accordance with the decrease in the output torque of the engine 1, so that the friction engagement element The shock at the time of fastening, that is, the shift shock is less likely to occur, and
By shifting the shift point to the high speed side, shifting is performed with a larger accelerator opening than in the case of lowland, and shift control is performed corresponding to the actual output torque T _e1 of the engine 1.

As described above, in the shift control device for the automatic transmission of the first embodiment, the engine 1 is based on the turbine speed n _p of the torque converter 2a, the engine speed n _e, and the capacity τ of the torque converter 2a. The actual torque T _e1 is calculated and the running state is determined from the difference between the actual torque T _e1 and the estimated torque T _e2 of the performance of the engine 1. Therefore, the driving state of the engine 1 can be detected with high accuracy. Is obtained.

Further, as the input means for detecting the running state, only the engine rotation sensor 10, the vehicle speed sensor 13 and the turbine sensor 14 which have been conventionally used as the input means of the automatic transmission 2 are used. Since there is no need to add a new input means, the effect of not increasing the number of assembly steps can be obtained, and the speed change of the automatic transmission 2 according to the running condition (low altitude / high altitude condition) can be achieved. Since the control can be performed only by the processing in the AT control unit 6, the automatic transmission 2 and the AT control unit 6 alone are completed as a product, so that an effect that the degree of completion as a product is increased can be obtained.

Next, the second invention corresponding to the invention of claim 6
Examples will be described. In describing the second embodiment, the description of the same points as in the first embodiment will be omitted, and only the differences will be described.

In the second embodiment, the AT control unit 6 detects the driving state (running state) of the engine 1. The detection result is output to the engine control unit 20, and the detection result is detected by the engine control unit 20. This is different from the first embodiment in that the control according to the above is performed. That is, as shown in FIG. 10, which is a flowchart showing the control flow of the AT control unit 6 and the engine control unit 20 of the second embodiment device, in step S27 subsequent to step S6, the torque difference T obtained in step S6 is obtained.
It is configured to transfer _e2-1 to the engine control unit 20.

Further, the engine control unit 20
Then, based on the signal indicating the torque difference T _e2-1 transferred from the AT control unit 6, the torque difference T _e2-1
Drive control is performed to increase the advance angle of the engine 1, the boost pressure, or the fuel supply amount such that
This control is performed in the engine control unit 20 as described above, but for convenience sake, it is shown as step S28 following S1 to step S27 which is the control of the AT control unit 6 in FIG.

By the drive control by the engine control unit 20, even if the air density changes due to traveling at high altitude, the engine torque characteristic as shown in FIG. 9 can be obtained, so that the AT control unit 6 can perform the same control as in the low altitude. Even if it goes, control will be performed according to the output torque of the engine. Therefore, in the case of the second embodiment, the AT control unit 6 stores only the lowland shift schedule of FIG. 5A and the lowland line pressure characteristic of FIG.

As described above, it is possible to obtain the effect that the shift control corresponding to the engine torque can be performed without changing the shift control of the AT control unit 6 even in the high-altitude running state.

Although the embodiment has been described above, the specific configuration is not limited to this embodiment, and the present invention includes a design change and the like within the scope not departing from the gist of the invention.

For example, in the first embodiment, the selection of both the shift schedule and the line pressure characteristic is switched depending on whether the vehicle is in the lowland traveling state or the highland traveling state. At least one of the characteristics may be switched.

In the second embodiment, the drive of the engine 1 is controlled by the engine control unit 20 so that the torque difference T _e2-1 becomes 0. For example, in the flowchart of FIG. N in S7
When it is determined to be O, the drive control of the normal (for lowland) engine 1 is performed, but when it is determined to be YES in step S7, the advance angle of the engine 1 is increased by a predetermined amount from the normal, or The drive control may be performed by increasing the supercharging pressure or the fuel supply amount. Note that such control corresponds to the invention of claim 5.

In the second embodiment, the torque difference T _e2-1 is _calculated by the AT control unit 6 and is transferred to the engine control unit 20, but the torque difference T _{e2 is calculated} in the engine control unit 20. You may ask for _-1 .

[0051]

As described above, in the traveling state detecting device according to the first aspect, the speed ratio of the torque converter is obtained by detecting the engine speed and the turbine speed.
While the actual torque is obtained based on the known stable torque converter capacity characteristics, the estimated torque is obtained based on the known engine torque characteristics, and the running state is determined from the relationship between the actual torque and the estimated torque. Since it is determined whether the vehicle is traveling at low altitude or traveling at high altitude, the effect that the traveling condition can be detected with high accuracy can be obtained.

According to another aspect of the present invention, there is provided a control device for an automatic transmission according to the first aspect, which is based on the detection result of the traveling state detecting device having a high traveling state detection accuracy. Since the shift control of 1 and the shift control for high altitudes are switched, it is possible to obtain the effect that the shift control corresponding to the engine torque can be performed with high accuracy.

According to a fifth aspect of the present invention, there is provided a control device for an engine according to the first aspect of the present invention, wherein the driving state of the engine is determined based on the detection result of the traveling state detecting device with high detection accuracy of the traveling state. Since it is configured to be switched to the normal mode, it is possible to obtain an effect that the driving state of the engine can be controlled with high accuracy.

Further, in the engine control apparatus according to the sixth aspect, the speed ratio of the torque converter is obtained by detecting the engine speed and the turbine speed, and the stable capacity characteristic of the torque converter which is known in advance is obtained. While the actual torque is obtained based on this, the estimated torque is obtained based on the engine torque characteristic that is known in advance, and the engine drive control means controls the drive of the engine so that the difference between the actual torque and the estimated torque becomes zero. With this configuration, the engine torque with respect to the engine speed can be made constant even when the running state changes between lowland and highland. Therefore, in the automatic transmission, it is not necessary to change the control depending on the difference between low altitude and high altitude.

[Brief description of drawings]

FIG. 1A is a claim correspondence diagram showing a traveling state detection device, an automatic transmission control device, and an engine control device according to claims 1 to 5, and FIG. 1B is an engine according to claim 6; It is a claim correspondence diagram showing the control device.

FIG. 2 is a schematic view showing a main part of the first embodiment device.

FIG. 3 is a fastening operation diagram of an automatic transmission to which the device of the first embodiment is applied.

FIG. 4 is a block diagram showing the overall configuration of the first embodiment device.

FIG. 5 is a shift schedule diagram of the device of the first embodiment.

FIG. 6 is a line pressure characteristic diagram of the first embodiment device.

FIG. 7 is a flowchart showing the control flow of the AT control unit of the first embodiment device.

FIG. 8 is a capacity characteristic diagram with respect to a speed ratio of the torque converter of the first embodiment device.

FIG. 9 is a torque characteristic diagram with respect to the engine speed of the first embodiment device.

FIG. 10 is a flowchart showing the control flow of the second embodiment device.

[Explanation of symbols]

AT automatic transmission TC torque converter E engine a Turbine rotation speed detection means b Engine speed detection means c storage means d Running state determination means e Shift control means f Engine drive control means d2 torque difference calculation means f2 engine drive control means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI F16H 59:38 F16H 59:38 59:42 59:42 (56) Reference JP-A-1-98753 (JP, A) JP 60-146949 (JP, A) JP 3-189459 (JP, A) JP 5-99320 (JP, A) JP 6-17684 (JP, A) JP 5-296886 (JP , A) Actual Kaihei 6-25656 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01L 5/00 F02D 29/00 F16H 59/14 F16H 59/16 F16H 59/38 F16H 59/42 F16H 61/02

Claims (6)

(57) [Claims] 1. A turbine speed detecting means for detecting a turbine speed of a torque converter of an automatic transmission, an engine speed detecting means for detecting an engine speed of an engine transmitting torque to the automatic transmission, A storage unit that stores capacity characteristics with respect to speed ratio of the torque converter and engine torque characteristics with respect to engine rotation speed, and obtains a speed ratio of the torque converter based on the detected engine rotation speed and turbine rotation speed. While calculating the actual torque based on the ratio and the capacity characteristic, the estimated torque is obtained from the engine speed and the engine torque characteristic, and when the difference between the actual torque and the estimated torque is less than a predetermined value, it is determined that the vehicle is in a lowland running state. In addition, the vehicle is equipped with a traveling state determination means for determining that the vehicle is traveling in a highland when the vehicle exceeds a predetermined value. A running state detection device characterized by being present. 2. A shift control means for performing shift control for lowland when detecting a lowland traveling state and for performing shift control for highland when detecting a highland traveling state based on the detection of the traveling state detecting device according to claim 1. An automatic transmission control device characterized by being provided. 3. The shift control means, based on a lowland map relating to at least one of hydraulic pressure and shift points according to engine torque characteristics in lowlands, and a highland map according to engine output torque decrease in highlands. The control device for an automatic transmission according to claim 2, wherein the control device is configured to perform the following. 4. The control device for an automatic transmission according to claim 2, wherein the shift control means is configured to perform learning control according to a decrease in output torque of an engine in a highland when a highland traveling is detected. . 5. An engine control device comprising an engine drive control means for performing drive control for high altitudes when a high altitude traveling condition is detected based on the detection of the traveling condition detecting device according to claim 1. . 6. A turbine speed detecting means for detecting a turbine speed of a torque converter of an automatic transmission, an engine speed detecting means for detecting an engine speed of an engine transmitting torque to the automatic transmission, A storage unit that stores capacity characteristics with respect to speed ratio of the torque converter and engine torque characteristics with respect to engine rotation speed, and obtains a speed ratio of the torque converter based on the detected engine rotation speed and turbine rotation speed. A torque difference calculation means for calculating an actual torque based on the ratio and the capacity characteristic, while obtaining an estimated torque from the engine speed and the engine torque characteristic, and obtaining a difference between the actual torque and the estimated torque; Drive control for controlling engine drive so that the difference between the estimated torque and the estimated torque is zero Control apparatus for an engine, characterized in that it comprises a stage, a.