JP3757017B2 - Shift control device for automatic transmission for vehicle - Google Patents

Description

【００４４】
ステップＳ２６では、上記のようにして算出された車両負荷度αVL（車両負荷情報）が大（正に大）であり且つアクセル開度ＶＡ（加速意思の大きさ）が大であって当該アクセル開度情報ＶＡに基づくアクセル開度変化ΔＶＡ（加速意思の大きさ）が大（正に大）であり且つ車速Ｖが小であるか否かを判別する（加速意思検出手段）。当該判別結果が真（Ｙｅｓ）で、車両負荷度αVLが大であり且つアクセル開度ＶＡ及びアクセル開度変化ΔＶＡが大であり且つ車速Ｖが小である場合には、次にステップＳ２８に進む。
【００４５】
ステップＳ２８では、変速段を２速段（目標変速段よりも低速段側の最適変速段）にすべく変速制御を実施する。つまり、ここでは、低車速で車両負荷度αVLが大であり且つアクセル開度ＶＡ及びアクセル開度変化ΔＶＡが大であるような場合は、車両重量（乗員数等）が大きく或いは道路状況が変化しており（降坂路から平坦路、平坦路から登坂路等）、運転者の加速意思が大で大きな加速トルクを必要としている状況とファジイ推論でき、このような場合には、上記表１の第１のファジイルールＲ1に基づき、上記ステップＳ２４で設定した目標変速段に拘わらず、変速段を通常の走行状態で使用する変速段のうち最も大きなトルクを発生可能な２速段（最適変速段）に変速することを決定する。
【００４６】
そして、次のステップＳ２９で、変速段制御部１３０において、２速段（最適変速段）への変速段制御を実施する。
これにより、通常再加速時において運転者はレスポンスのよい加速を望む傾向にあり、その際車両は大きな加速トルクを必要とするのであるが、このような場合であっても、変速段が速やかに２速段（最適変速段）に変速制御されることになり、減速から再加速に移行する際のドライバビリティが向上する。つまり、Ｄレンジで自動変速制御が実施されていても、運転者の意思に応じてマニュアル操作を行った場合と略等しく変速段を２速段として大きな出力トルクを得ることができるのである。
【００４７】
また、この場合、ステップＳ２４で目標変速段が設定された後、直ちにファジイ制御（ステップＳ２６、ステップＳ２８）に基づき変速段制御部１３０において変速段が最適変速段である２速段まで速やかに切換えられるので、例えば変速が１段ずつ段階的に順次実施されるようなことがなく、故に運転者が不愉快なシフトショックやタイムラグを感じるようなことが極力防止される。
【００４８】
つまり、車両がバスの場合にあっては、図５に示すように、アクセルペダル７０がオフ状態でＡ1位置まで比較的大きく減速したとしても、上述したように４速段が低速領域まで保持され、再加速が行われるとアクセル開度ＶＡの増加に伴いポイントがＡ2位置に移行し目標変速段が加速マップ上で３速段とされるのであるが、この時点で車両負荷度αVLが大で且つアクセル開度ＶＡ及びアクセル開度変化ΔＶＡが大と判定されると、目標変速段の３速段に拘わらず変速段が一気にワンモーションでもって４速段から最適変速段である２速段まで切換えられることになり、スムースにして速やかに大きな出力トルクが発生可能とされるのである。
【００４９】
そして、次のステップＳ３６では、上記ステップＳ２０においてクラッチ断とされていたクラッチ装置３を接続状態に戻すべくクラッチ接とする。このように、一旦クラッチ装置３が断状態とされた後、最適変速段である２速段への変速が完了するまでまでクラッチ断状態を保持し、変速完了時点で初めてクラッチ接とすることにより、例えば上記のように４速段から２速段に変速する場合のように現在の変速段と最適変速段との差が２段以上であっても１段毎にクラッチの断接が行われることがなく、故にクラッチの接続時に発生するショックが極力防止される。なお、クラッチ断とされていない場合にはクラッチ装置３はそのまま接続状態に保持される。
【００５０】
ところで、上記第１のファジイルールＲ1の前件部の条件が満たされなくなると当該第１のファジイルールＲ1はもはや成立しなくなる。しかしながら、再加速中、例えば登坂路走行中であって乗員の人数が多く車両負荷度αVLが大きいような場合には、実際には依然として大きな出力トルクを必要としている場合が多い。
【００５１】
従って、ステップＳ２６の判別結果が偽（Ｎｏ）と判別された場合には、次のステップＳ３０において、今度は上記表１に示す第２のファジイルールＲ2に基づいてファジイ推論を行い、現在の変速段が目標変速段よりも小（現段＜目標段）で且つ相変わらず上記車両負荷度αVLが大（正に大）であるか否かを判別する。
【００５２】
目標変速段が３速段である一方で第１のファジイルールＲ1に基づき最適変速段が２速段とされている場合には現在の変速段は目標変速段よりも小（現段＜目標段）である。従って、アクセル開度ＶＡ或いはアクセル開度変化ΔＶＡが小とされて上記第１のファジイルールＲ1の条件を外れた時点で相変わらず車両負荷度αVLが大きければ、ステップＳ３０の判別結果は真（Ｙｅｓ）であり、このような場合には、次のステップＳ３２において現段保持制御を行う。つまり、ステップＳ３２では、第２のファジイルールＲ2に基づき、目標変速段に拘わらず変速段を現在の変速段（ここでは２速段）に保持（現段保持）することを決定する。
【００５３】
そして、次のステップＳ３３で、変速段制御部１３０において、変速段を現段に保持する。
これにより、車両負荷度αVLが大きいような場合であっても、再加速中にトルク不足となってしまうことが好適に防止され、加速走行を良好に継続することができる。
【００５４】
一方、ステップＳ３０の判別結果が偽（Ｎｏ）で、第２のファジイルールＲ2が成立せず現在の変速段が目標変速段よりも小（現段＜目標段）である一方で例えば車両が平坦路走行或いは降坂路走行となり車両負荷度αVLが減少したような場合には、もはや大きな出力トルクは必要ないと判定できる。従って、このような場合には、次にステップＳ３４に進み、変速段制御部１３０において、上記図５の加速マップに基づく通常の変速段制御を行う。
【００５５】
以上、説明したように、本発明の車両用自動変速機の変速制御装置では、車両が減速した後に再加速するような場合において、低車速で車両負荷度αVLが大きく且つアクセル開度ＶＡ及びアクセル開度変化ΔＶＡが大であって、つまりファジイ推論により第１のファジイルールＲ1が成立するような場合には、変速段を目標変速段に拘わらず目標変速段よりも低速段側の２速段（最適変速段）とするようにしている。
【００５６】
従って、乗員の人数或いは荷物の積載量が多いような場合、或いは車両が登坂路を走行している場合であっても、運転者が減速後にトルクフルな加速を望むようなときにおいて高い出力トルクで速やかに車両を加速させることが可能となる。特に、本発明を減速と加速を頻繁に行う一方で乗員の増減の激しい路線バス等に適用するようにすれば、減速時には比較的低車速まで変速（シフトダウン）を実施しないようにしてシフトショックを低減可能であるとともに（図５の減速マップ参照）、再加速時にあっては乗員の人数（重量）に拘わらずトルク不足なく極めて良好な加速を行うことが可能とされる。
【００５７】
この際、再加速時の変速段が例えば４速段であるような場合にあっては、４速段から２速段まで一気に２段階飛び越し変速することが可能であるので、１段ずつ段階的に変速を行う場合と異なりシフトショックなくレスポンスのよいスムースな加速が実現可能とされる。
また、変速段を２速段とした後、さらに継続して大きな出力トルクが必要な場合には、第２のファジイルールに基づき２速段（最適変速段）とされた変速段が良好に継続維持されるので、トルクフルな加速が充分に実施されることになる。
【００５８】
なお、上記実施例では、車両負荷度αVLが大きく且つアクセル開度ＶＡ及びアクセル開度変化ΔＶＡが大である場合には、第１のファジイルールＲ1の後件部に示すように最適変速段を２速段としたが、この最適変速段、即ち第１のファジイルールＲ1の後件部を例えば「目標変速段より１段以上低速段」としてもよい。この場合、１段だけ低速段にすればよいのか或いは２段階以上低速段にする必要があるのかが問題となるが、これについては、第１のファジイルールＲ1の後件部の適合度の出力値に応じて決定すればよい。このようにすれば、上記実施例で示したように、例えば４速段（図５中のＡ1位置）で再加速を開始した場合に限られず、それ以外の変速段（例えば、５速段等）で再加速を行った場合でもトルク不足のないスムースな加速を実現することができる。
【００５９】
また、上記実施形態においては、ファジイ推論法を用いるようにしているが、このようなファジイ推論を行うことなく単に閾値判別によって２速段（最適変速段）にすべきか否の判別を行うようにしても同様の効果が得られる。
また、上記実施形態においては、自動変速機として機械式の歯車式変速機４を用いるようにしたが、これに限られず、当該変速制御装置を、通常乗用車に搭載されるようなトルクコンバータと遊星歯車からなる自動変速機に適用することも可能である。
【００６０】
また、上記チェンジレバー６０には、Ｎ（ニュートラル）レンジ、Ｒ（リバース）レンジ及びＤ（ドライブ）レンジの他、１速段〜５速段の各Ｍ（マニュアル）レンジも設けられており、上記自動変速のみならず手動での変速も可能とされている。なお、チェンジレバー６０は、これら１速段〜５速段の各Ｍレンジに代えてＭレンジが現変速段ホールド位置から変速段をアップ（＋）及びダウン（−）指示して変速段を切換え操作するようなタイプのものであってもよい。
【００６１】
【発明の効果】
以上、詳細に説明したように、本発明の請求項１の車両用自動変速機の変速制御装置によれば、車速とアクセルペダルの操作状態とに応じて予め設定されたシフトマップに基づいて目標変速段を設定する一方、アクセルペダルのオフ状態からオン状態への移行時には、目標変速段に優先して運転者の加速意思の大きさ及び車両負荷状態を入力パラメータとするファジイ推論に応じたきめ細かな最適変速段で変速制御を行うことができ、これにより、車両負荷が大きい場合、例えば車両重量（乗員数等）や勾配抵抗が大きい場合、再加速を行う際の運転者の加速意思が大である場合には、通常の目標変速段よりもより大きな駆動トルクを発生可能となり、車両のトルク不足を防止してトルクフルな再加速走行を実現することができ、ドライバビリティを向上させることができる。
【００６２】
また、本発明では、現在の変速段と最適変速段との差が２段以上であっても、一気に飛び越し変速が実現されるので、１段ずつ段階的に変速が実施されるときのようなシフトショックもなく、レスポンスよくスムースに変速を達成できる。また、請求項２の車両用自動変速機の変速制御装置によれば、加速意思の大きさをアクセル開度及びアクセル開度変化から容易に求めることができ、最適変速段を容易に設定することができる。
【図面の簡単な説明】
【図１】本発明に係る変速制御装置が適用される車両の駆動系の全体構成を示す図である。
【図２】本発明に係る減速再加速制御の制御ルーチンを示すフローチャートの一部である。
【図３】図２に続く、減速再加速制御の制御ルーチンを示すフローチャートの残部である。
【図４】変速制御手順を示す制御ブロック図である。
【図５】目標変速段設定用のシフトマップ（減速マップ及び加速マップ）を示す図である。
【符号の説明】
１ ディーゼルエンジン
３ クラッチ装置
４ 変速機
８ エンジン回転センサ
６８ ギヤ位置センサ
７０ アクセルペダル
７２ アクセル開度センサ（アクセル操作状態検出手段）
７８ 車速センサ（車速検出手段）
８０ 電子制御ユニット（ＥＣＵ）
９０ 判断部
１００ 車両負荷度算出部（負荷状態検出手段）
１１０ 目標変速段設定部（目標変速段設定手段）
１２０ 最適変速段決定部（最適変速段設定手段）
１３０ 変速段制御部（変速段制御手段）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shift control device for an automatic transmission for a vehicle, and more particularly to a shift control device that improves acceleration performance during vehicle deceleration reacceleration control.
[0002]
[Related background]
2. Description of the Related Art Conventionally, automatic transmissions that automate shifting operations have been frequently used as transmissions for vehicles. In the case of a small vehicle, this automatic transmission is mainly used in which a torque converter is used instead of the clutch. However, in large vehicles such as buses and trucks, the amount of driving torque transmitted is large, and it is difficult for the torque converter to sufficiently transmit the driving torque.
[0003]
In view of this, an automatic transmission using a mechanical transmission similar to a manual transmission and having a clutch device that can be automatically connected to and disconnected from the transmission has been developed for large vehicles. As a result, even when the transmission drive torque is large, it is possible to automatically perform a shift by automatically controlling the clutch in accordance with the shift timing. Further, in such an automatic transmission with a clutch, when the vehicle decelerates, the clutch is automatically disconnected in order to avoid engine stall.
[0004]
Furthermore, when the clutch is automatically disengaged in this way, the clutch is disengaged so that when the clutch is reconnected, the gear position of the automatic transmission is in accordance with the vehicle speed at that time. Japanese Patent Publication No. 5-80374 discloses a device configured so that the gear position is switched and controlled according to the vehicle speed.
[0005]
[Problems to be solved by the invention]
By the way, in a bus or a truck, the vehicle load greatly increases or decreases due to a change in the load weight (number of passengers, etc.) on the vehicle, that is, a change in the vehicle weight or a change in road conditions. Therefore, for example, in the case of a bus, when the number of passengers increases, the vehicle requires a larger output torque than when the number of passengers is small. Also, when the vehicle is traveling on a flat road than when it is traveling on a downhill road, the output torque is greater when traveling on an uphill road than when traveling on a flat road. Need. This tendency is particularly noticeable when the vehicle is re-accelerated from a low speed after starting or after decelerating, that is, when the clutch is automatically disengaged as described above.
[0006]
However, the apparatus disclosed in the above publication merely controls the shift stage according to the vehicle speed, and does not switch the shift stage in consideration of the vehicle load information as described above. . Therefore, in the apparatus disclosed in the above publication, when the loaded weight (the number of passengers) is large, there is a possibility that the output torque becomes insufficient against the intention of the driver when the clutch is engaged and reacceleration is performed. Thus, if the output torque is insufficient, smooth acceleration cannot be performed, which is not preferable.
[0007]
The present invention has been made based on the above-described circumstances, and an object of the present invention is to provide an automatic transmission for a vehicle capable of realizing smooth reacceleration according to the driver's intention during deceleration reacceleration regardless of the vehicle load. Another object of the present invention is to provide a shift control device for a machine.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, vehicle speed detection means for detecting the vehicle speed, accelerator operation state detection means for detecting the operation state of the accelerator pedal, the vehicle speed and the operation state of the accelerator pedal are provided. A target shift speed setting means for setting a target shift speed based on the above, an acceleration intention detection means for detecting a driver's intention to accelerate, a load state detection means for detecting a load state of a vehicle, and the accelerator operation state detection means An optimal shift speed setting means for setting an optimal shift speed based on at least the magnitude of the driver's intention to accelerate and the vehicle load condition when a shift from an off state to an on state of the pedal is detected; and the target shift speed Shift control is performed according to the target shift stage from the setting means, and the accelerator pedal is turned on from the off state by the accelerator operation state detection means. If the transition to state is detected, the shift speed control means for shifting control according to the optimum gear from the priority to the optimum gear setting means to the target gearThe target shift speed setting means sets the target shift speed based on a shift map set in advance according to the vehicle speed and the operation state of the accelerator pedal, and the optimal shift speed setting means at least The optimum gear position is set based on fuzzy inference using the magnitude of intention to accelerate and the vehicle load state as input parameters.It is characterized by that.
[0009]
Therefore,The target shift speed setting means sets the target shift speed based on a shift map set in advance according to the vehicle speed and the accelerator pedal operation state, while the optimal shift speed setting meansAt least the driver's intention to accelerate and the vehicle load statusFuzzy inference with inputIf the shift from the OFF state of the accelerator pedal to the ON state is detected while the vehicle is traveling, the shift at the optimal shift stage is performed in preference to the target shift stage.
[0010]
As a result, when the accelerator pedal is not operated and the vehicle decelerates once, the vehicle load is large, that is, the vehicle weight (number of passengers, etc.) is large or the road conditions are changing (from downhill road to flat road, On flat roads and uphill roads, etc., the next time re-acceleration requires a relatively large output torque, the driver will depress the accelerator pedal greatly. By switching the gear stage to a low speed stage, for example, from a normal target gear stage, it becomes possible to generate a larger driving torque, preventing a torque shortage of the vehicle and realizing a torque-full reacceleration running.
In addition, by setting the optimum shift stage using fuzzy inference with input parameters such as the magnitude of intention to accelerate (accelerator opening, change in accelerator opening) and vehicle load conditions, the optimum shift stage is set finely. Thus, the shift control according to the driver's intention is performed more accurately, and a suitable reacceleration running is realized.
[0011]
In particular, in the present invention, even if the difference between the current shift speed and the optimum shift speed is two or more, the jumping is realized at a stretch, so that the shift is executed step by step step by step. There is no shift shock and the shift is achieved smoothly with good response.
In the invention of claim 2, the accelerator operation state detecting means detects accelerator opening and accelerator opening change,The acceleration intention detection means includesAcceleration intention sizeTheAccording to the accelerator opening and accelerator opening changeDetectIt is characterized by that.
[0012]
Therefore, the magnitude of the intention to accelerate is easily obtained from the accelerator opening and the change in the accelerator opening, and the optimum gear position is easily set..
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, with reference to the drawings, an example as an embodiment of the present invention will be described in detail.
FIG. 1 shows an overall configuration of a drive system of a vehicle (such as a bus) to which a shift control device according to the present invention is applied. Hereinafter, the configuration of the drive system of the vehicle including the speed change control device will be described with reference to FIG.
[0015]
Referring to FIG. 1, an engine output shaft 2 extends from a diesel engine (hereinafter referred to as an engine) 1, and this engine output shaft 2 is connected to a gear type transmission (hereinafter simply referred to as a transmission) via a clutch device 3. Connected to 4). As a result, the output of the engine 1 is transmitted to the transmission 4 via the clutch device 3, and a shift is performed in the transmission 4. The transmission 4 is an automatic transmission that has five forward speeds (first speed to fifth speed) in addition to the reverse speed, and is capable of manual shift as well as automatic shift. . The clutch device 3 is configured such that when the transmission 4 is automatically shifted, the connection / disconnection control is automatically performed accordingly, and the details will be described later.
[0016]
The engine 1 is provided with a fuel injection pump (hereinafter referred to as an injection pump) 6 for supplying fuel to the engine 1. The injection pump 6 is a device that injects fuel by operating the pump by the output of the engine 1 transmitted through a pump input shaft (not shown). The injection pump 6 is provided with a control rack (not shown) for adjusting the fuel injection amount, and further provided with a rack position sensor 9 for detecting a rack position (control rack position) SRC of the control rack. It has been. In addition, an engine rotation sensor 8 for detecting the rotation speed of the pump input shaft and detecting the rotation speed of the output shaft 2 of the engine 1, that is, the engine rotation speed Ne, is attached near the pump input shaft. Yes.
[0017]
The clutch device 3 is a normal mechanical friction type clutch that is brought into a connected state by pressing a clutch plate 12 to a flywheel 10 by a pressure spring 11 while being disconnected by separating the clutch plate 12 from the flywheel 10. This operation can be performed automatically. That is, the air cylinder unit 16 that functions as a clutch actuator for connecting and disconnecting the clutch is connected to the clutch plate 12 via the outer lever 12a.
[0018]
An air tank 34 is connected to the air cylinder unit 16 via an air passage 30 that is an air supply passage. Accordingly, when air is supplied from the air tank 34 via the air passage 30, the air cylinder unit 16 automatically operates. As a result, the clutch plate 12 moves and the clutch is automatically engaged / disengaged.
[0019]
The clutch device 3 is provided with a clutch stroke sensor 17 for detecting a movement amount of the clutch plate 12, that is, a clutch stroke amount SCL. The input shaft 20 of the transmission 4 is provided with a clutch rotation sensor 22 that detects the rotation speed of the input shaft 20, that is, the clutch rotation speed NCL.
The change lever 60 is a select lever of the transmission 4 and is provided with an N (neutral) range, an R (reverse) range, and a D (drive) range corresponding to the automatic transmission mode.
[0020]
The change lever 60 is provided with a select position sensor 62 for detecting each range position. The select position sensor 62 is connected to the ECU 80. On the other hand, the ECU 80 is connected to a gear shift unit 64 for switching the meshing of the gear of the transmission 4, that is, the gear position. Thus, a drive signal is supplied from the ECU 80 to the gear shift unit 64 in response to the position signal from the select position sensor 62, and the gear position of the transmission 4 is switched according to the selected select range. When the select position is in the D range, the gear position is switched according to automatic shift control described later.
[0021]
The gear shift unit 64 includes a plurality of solenoid valves (only one is shown in FIG. 1) 66 that operates in response to an operation signal from the ECU 80, and a plurality of power cylinders that operate a shift fork (not shown) in the transmission 4. (Not shown). These power cylinders of the gear shift unit 64 are connected to the above-described air passage 30 via the electromagnetic valve 66 and the air passage 67, and thus operate when high-pressure operating air is supplied from the air tank 34. That is, when an operation signal is given to the electromagnetic valve 66 from the ECU 80, each power cylinder is operated in accordance with the operation signal, whereby the meshing state of the gear transmission 4 is appropriately changed.
[0022]
In the vicinity of the gear shift unit 64 of the transmission 4, a gear position sensor 68 for detecting each gear position is attached. The gear position sensor 68 outputs a current gear position signal, that is, a gear position signal, to the ECU 80. Is done.
The accelerator pedal 70 is provided with an accelerator opening sensor (accelerator operation state detecting means) 72. The accelerator opening sensor 72 outputs the depression amount of the accelerator pedal 70, that is, the accelerator opening VA. A vehicle speed sensor (vehicle speed detection means) 78 for detecting the vehicle speed V is attached to the output shaft 76 of the transmission 4. Further, the brake pedal 50 is provided with a brake sensor 52.
[0023]
Reference numeral 82 in FIG. 1 indicates an engine control unit provided separately from the ECU 80. The engine control unit 82 is a device that supplies a signal from the ECU 80 according to information from each sensor, accelerator opening information VA, and the like to an electronic governor (not shown) in the injection pump 6. Drive control is performed. That is, when a command signal is supplied from the engine control unit 82 to the electronic governor, the control rack is operated to increase or decrease the fuel, and the increase or decrease of the engine rotational speed Ne is controlled.
[0024]
The ECU 80 includes a microcomputer (CPU), a memory, an interface that performs input / output signal processing, and the like.
On the input side of the ECU 80, the engine rotation sensor 8, rack position sensor 9, clutch stroke sensor 17, clutch rotation sensor 22, brake sensor 52, select position sensor 62, gear position sensor 68, accelerator position sensor 72, and vehicle speed are described above. Sensors 78 and the like are connected to each other, and information from each of these sensors and the like is input.
[0025]
On the other hand, the above-described solenoid valve 66, engine control unit 82, and air cylinder unit 16 are connected to the output side of the ECU 80.
Incidentally, in the memory of the ECU 80, when the selected position is in the D range, a shift map for determining the target gear position based on the vehicle speed V, the accelerator opening degree VA, and the engine rotational speed Ne (FIG. 5). Reference) is stored. Accordingly, in the D range, the ECU 80 normally gives a shift signal corresponding to the target shift stage to each electromagnetic valve 66 of the gear shift unit 64, whereby the gear position is switched to the target shift stage. Then, automatic shift control is performed.
[0026]
As described above, when the gear of the transmission 4 is switched to the target shift speed and the shift is completed, the gear position signal is output from the gear position sensor 68, thereby making it possible to recognize the current shift speed and the shift signal. On the other hand, it is possible to confirm whether or not the gear position has been switched reliably, that is, whether or not the meshing is in a normal state.
When the target shift speed is determined as described above, the ECU 80 supplies a shift signal corresponding to the target shift speed to each electromagnetic valve 66 of the gear shift unit 64 and also supplies a drive signal to the air cylinder unit 16. . As a result, the air cylinder unit 16 automatically operates simultaneously with the start of the shift, the clutch plate 12 is separated from the flywheel 10, and the clutch device 3 is disconnected. After that, when shifting is achieved, the air cylinder unit 16 returns to operate, the clutch plate 12 is pressed against the flywheel 10, and the clutch device 3 is brought into the connected state again.
[0027]
Hereinafter, the operation according to the present invention of the shift control apparatus configured as described above will be described.
2 and 3, there is shown a flowchart of a deceleration reacceleration control routine executed by the ECU 80 when acceleration is performed after deceleration in the automatic shift control in the D range, and with reference to FIG. 4, A block diagram of shift control using fuzzy control, that is, a block diagram showing the concept of the present invention is shown. Referring to FIG. 5, a shift map for setting a target shift stage is shown. In the shift map, only the shift pattern from the second speed to the fourth speed is shown for convenience of explanation.
[0028]
First, the outline procedure of the shift control will be briefly described with reference to FIG. 4. The target shift speed setting unit (target shift speed setting means) 110 sets the target shift speed by input from various sensors. Meanwhile, judgmentPart 90 is the vehicle load calculation unit(Load state detection means)100 and optimum gear stage determination unit(Optimum gear position setting means)120, the optimum gear stage determination unit 120 includes a vehicle load degree αVL (vehicle load state) calculated by the vehicle load degree calculation unit 100 and a target shift set by the target gear stage setting unit 110. The optimum gear is set based on the gear. Then, the gear stage control unit (gear stage control means) 130 controls the gear stage of the transmission 4 to the optimum gear stage based on the output information from the optimum gear stage determining unit 120.
[0029]
Hereinafter, the deceleration reacceleration control according to the present invention will be described in detail with reference to the flowcharts of FIGS.
In step S10 of FIG. 2, detection information from the various sensors is read.
In the next step S12, the vehicle load degree αVL (vehicle load state) is calculated in the vehicle load degree calculation unit 100 in FIG. The vehicle load degree αVL is a parameter corresponding to the weight of the vehicle and the gradient resistance of the vehicle, and is mainly based on the rack position signal SRC from the rack position sensor 9, the engine rotation speed information Ne from the engine rotation sensor 8, and the vehicle speed sensor 78. And the vehicle speed information V.
[0030]
Specifically, the vehicle load degree αVL is calculated by the following procedure.
First, the engine torque Te is calculated from the rack position signal SRC and the engine rotational speed information Ne from a preset map or the like, and the driving force F of the vehicle is calculated from the engine torque Te by the following equation (1), for example.
F = (Te · it · if · η) / rw (1)
Here, it is the gear ratio of the gear stage, if is the final reduction gear ratio (differential gear ratio), η is the power transmission efficiency, and rw is the tire moving radius.
[0031]
On the other hand, the air resistance Rl of the vehicle is calculated. Here, the air resistance Rl as the running resistance of the vehicle is calculated from the vehicle speed information V from the following equation (2).
Rl = λ ・ As ・ V²… (2)
Here, λ is an air resistance coefficient, and As is the front projected area of the vehicle.
Next, a straight flat road empty vehicle equivalent acceleration α0 is calculated from the following driving force information F and air resistance information Rl from the following equation (3).
[0032]
α0 = g · {F− (μW0 + Rl)} / (W0 + Wr) (3)
Here, g is a gravitational acceleration, μ is a road surface friction coefficient, W0 is an empty weight, and Wr is a rotating part weight.
The vehicle load degree αVL is calculated from the following equation (4) from the straight flat road empty vehicle equivalent acceleration α0 and the actual acceleration information α obtained from the vehicle speed information V.
[0033]
αVL = α0−α (4)
As described above, the vehicle load degree information αVL corresponds to the weight of the vehicle and the gradient resistance of the vehicle. That is, if αVL> 0, the vehicle load is heavy, and if αVL <0, the vehicle load is light. Therefore, it is possible to determine how heavy (or light) the vehicle load is based on the value of αVL. For example, when the number of passengers (weight) on a bus is large or the vehicle is traveling on an uphill road, the vehicle load degree αVL is very large and the vehicle load is quite heavy.
[0034]
When the vehicle load degree αVL is calculated in this way, the process proceeds to step S14 to determine whether or not the accelerator pedal 70 is in an off state. Specifically, it is determined whether or not the accelerator opening signal VA from the accelerator opening sensor 72 is very small, for example, 10% or less of the fully opened state.
If the determination result in step S14 is true (Yes) and it is determined that the accelerator pedal 70 is in an off state (for example, an opening degree of 10% or less), the driver does not intend to accelerate and the vehicle is in a decelerating state. Can be determined. Accordingly, in this case, the process proceeds to step S16.
[0035]
In step S16, the target gear position setting unit (target gear position setting means) 110 in FIG. 4 uses the target map based on the deceleration map (shown by a broken line in FIG. 5) among the shift maps stored in the memory of the ECU 80. Set the gear position. That is, the target shift speed corresponding to the current vehicle speed V and accelerator opening VA is read from the deceleration map. When the normal vehicle is a bus, as shown in the deceleration map (broken line in FIG. 5), the target shift speed is such that the accelerator pedal 70 is off (for example, the opening degree is 10% or less) and the vehicle speed V is It is set so that the same shift stage is held for a long time to a relatively low speed range when it is lowered. As a result, even for a route bus that frequently decelerates and accelerates, the number of occurrences of shift shock due to acceleration / deceleration is reduced as much as possible, and the ride comfort is improved.
[0036]
In the next step S18, it is determined whether or not the engine speed Ne is equal to or less than a predetermined value Ne1. This determination is performed for the purpose of automatically putting the clutch device 3 in a disconnected state so as not to cause an engine stall when the engine speed Ne decreases. Here, the predetermined value Ne1 is set to a value (for example, 1500 rpm) slightly higher than the normally set idling speed.
[0037]
If the determination result in step S18 is true (Yes) and the engine speed Ne is less than or equal to the predetermined value Ne1, the routine proceeds to step S20, where the clutch is disengaged, that is, the clutch device 3 is automatically disengaged. That is, a drive signal is supplied from the ECU 80 to the air cylinder unit 16, and the clutch plate 12 is separated from the flywheel 10 by the air pressure from the air tank 34.
[0038]
In step S22, the shift speed control unit 130 in FIG. 4 performs shift speed control toward the target shift speed set based on the deceleration map as described above. That is, in step S22, a signal corresponding to the target shift speed is supplied from the ECU 80 to the electromagnetic valve 66, the engine control unit 82, and the air cylinder unit 16, respectively. As a result, the clutch device 3 is held in the disengaged state, and the gear position is controlled to be switched to a desired gear position based on the deceleration map. In this shift speed control, a subroutine (not shown) provided separately is actually executed.
[0039]
On the other hand, if the determination result in step S18 is false (No) and the engine speed Ne is greater than the predetermined value Ne1, it can be determined that there is no concern of engine stall. Accordingly, in this case, the process proceeds to step S22 without executing step S20, that is, without disengaging the clutch device 3, and the gear position control is also performed based on the deceleration map. However, in the gear position control, the clutch device 3 is naturally connected and disconnected as described above.
[0040]
By the way, the accelerator pedal 70 is once turned off (for example, the opening degree is 10% or less) (step S14), and after the gear position control (step S22) based on the deceleration map is performed, the accelerator pedal 70 is turned on again ( For example, when the so-called re-acceleration is performed with the opening degree being larger than 10%, the determination result in step S14 is false (No). Therefore, in this case, the process proceeds to step S24 in FIG.
[0041]
Thus, when the accelerator pedal 70 is in the on state, it can be determined that the driver has an intention to accelerate. Therefore, in step S24, the target shift speed setting unit 110 in FIG. 4 sets the target shift speed based on an acceleration map (shown by a solid line in FIG. 5) among the shift maps stored in the memory of the ECU 80. To do. That is, the target shift speed corresponding to the current vehicle speed V and accelerator opening VA is read from the acceleration map. When the target shift speed is obtained from the acceleration map, the process proceeds to step S26 and subsequent steps.
[0042]
Steps S26 to S32 are fuzzy control routines executed by the optimum gear position determination unit 120 of FIG. For the fuzzy inference in this fuzzy control, for example, a fuzzy inference method using a membership function is used.
Here, referring to Table 1, the fuzzy rules of the fuzzy control are shown, and will be described with reference to Table 1 below. Actually, a plurality of fuzzy rules are set in addition to those shown here, and various fuzzy controls are performed. However, since these are not related here, description thereof will be omitted.
[0043]
[Table 1]

[0044]
In step S26, the vehicle load degree αVL (vehicle load information) calculated as described above is large (exactly large) and the accelerator opening VA (magnitude of acceleration intention) is large, and the accelerator opening It is determined whether or not the accelerator opening change ΔVA (the magnitude of the acceleration intention) based on the degree information VA is large (exactly large) and the vehicle speed V is small.(Acceleration intention detection means). If the determination result is true (Yes), the vehicle load degree αVL is large, the accelerator opening VA and the accelerator opening change ΔVA are large, and the vehicle speed V is small, the process proceeds to step S28. .
[0045]
In step S28, gear shift control is performed so that the gear position is the second gear position (the optimum gear position on the lower speed side than the target gear position). That is, here, when the vehicle load degree αVL is large at a low vehicle speed and the accelerator opening VA and the accelerator opening change ΔVA are large, the vehicle weight (the number of passengers, etc.) is large or the road condition changes. (Downhill road to flat road, flat road to uphill road, etc.), the driver's willingness to accelerate is large and can be inferred from the fact that a large acceleration torque is required. Based on the first fuzzy rule R1, regardless of the target gear set in step S24, the second gear (optimum gear) that can generate the largest torque among the gears that are used in the normal driving state. ).
[0046]
In the next step S29, the shift speed control unit 130 performs shift speed control to the second speed (optimal shift speed).
As a result, during normal re-acceleration, the driver tends to desire a responsive acceleration, and the vehicle needs a large acceleration torque at that time. Shift control is performed to the second gear (optimal gear), and drivability when shifting from deceleration to reacceleration is improved. That is, even if the automatic shift control is performed in the D range, it is possible to obtain a large output torque with the shift speed set to the second speed substantially the same as when the manual operation is performed according to the driver's intention.
[0047]
Further, in this case, immediately after the target shift speed is set in step S24, the shift speed control unit 130 immediately switches to the second speed that is the optimal shift speed based on the fuzzy control (step S26, step S28). Therefore, for example, the shift is not performed step by step, and therefore, it is possible to prevent the driver from feeling unpleasant shift shock or time lag as much as possible.
[0048]
That is, when the vehicle is a bus, as shown in FIG. 5, even if the accelerator pedal 70 is off and the vehicle decelerates relatively to the A1 position, the fourth gear is maintained up to the low speed region as described above. When reacceleration is performed, the point shifts to the A2 position as the accelerator opening VA increases, and the target shift stage is set to the third speed stage on the acceleration map. At this point, the vehicle load degree αVL is large. If it is determined that the accelerator opening VA and the accelerator opening change ΔVA are large, the shift speed is changed from the 4th speed to the 2nd speed, which is the optimum speed, with one motion at a time regardless of the 3rd speed of the target speed. Thus, a large output torque can be generated smoothly and quickly.
[0049]
Then, in the next step S36, the clutch device 3 that has been disengaged in step S20 is engaged with the clutch so as to return to the engaged state. Thus, after the clutch device 3 is once disengaged, the clutch disengaged state is maintained until the gear shift to the second gear speed, which is the optimum gear position, is completed, and the clutch is engaged for the first time when the gear shift is completed. For example, even when the difference between the current gear and the optimum gear is two or more as in the case of shifting from the fourth gear to the second gear as described above, the clutch is connected / disconnected for each gear. Therefore, the shock that occurs when the clutch is engaged is prevented as much as possible. When the clutch is not disengaged, the clutch device 3 is kept in the connected state as it is.
[0050]
By the way, when the condition of the antecedent part of the first fuzzy rule R1 is not satisfied, the first fuzzy rule R1 is no longer established. However, during reacceleration, for example, when traveling on an uphill road and there are many passengers and the vehicle load degree αVL is large, in practice, a large output torque is still often required.
[0051]
Accordingly, if the determination result in step S26 is false (No), in the next step S30, fuzzy inference is performed based on the second fuzzy rule R2 shown in Table 1 above, and the current speed change is performed. It is determined whether or not the speed is smaller than the target shift speed (current speed <target speed) and the vehicle load degree αVL is still high (just high).
[0052]
If the target speed is 3rd speed and the optimum speed is 2nd based on the first fuzzy rule R1, the current speed is smaller than the target speed (current speed <target speed) ). Accordingly, if the vehicle load degree αVL is still large at the time when the accelerator opening VA or the accelerator opening change ΔVA is made small and deviates from the condition of the first fuzzy rule R1, the determination result in step S30 is true (Yes). In such a case, the current stage holding control is performed in the next step S32. That is, in step S32, based on the second fuzzy rule R2, it is determined that the gear position is held at the current gear stage (here, the second gear stage) (current stage is held) regardless of the target gear stage.
[0053]
Then, in the next step S33, the gear stage control unit 130 holds the gear stage at the current stage.
As a result, even when the vehicle load degree αVL is large, it is preferable to prevent the torque from being insufficient during re-acceleration, and the acceleration travel can be continued well.
[0054]
On the other hand, the determination result of step S30 is false (No), the second fuzzy rule R2 is not established, and the current shift speed is smaller than the target shift speed (current speed <target speed), while the vehicle is flat, for example. If the vehicle load degree αVL decreases due to road traveling or downhill traveling, it can be determined that a large output torque is no longer necessary. Therefore, in such a case, the process proceeds to step S34, where the shift speed control unit 130 performs normal shift speed control based on the acceleration map of FIG.
[0055]
As described above, in the shift control device for an automatic transmission for a vehicle according to the present invention, when the vehicle is re-accelerated after being decelerated, the vehicle load degree αVL is large at a low vehicle speed and the accelerator opening VA and accelerator When the opening change ΔVA is large, that is, when the first fuzzy rule R1 is established by fuzzy inference, the second speed stage on the lower speed side than the target speed stage regardless of the target speed stage. (Optimum shift speed).
[0056]
Therefore, even when the number of passengers or the load capacity of the baggage is large, or even when the vehicle is traveling on an uphill road, when the driver desires full acceleration after deceleration, the output torque is high. The vehicle can be accelerated quickly. In particular, if the present invention is applied to a route bus that frequently decelerates and accelerates while increasing or decreasing the number of occupants, the shift shock is avoided so as not to shift (shift down) to a relatively low vehicle speed during deceleration. (See the deceleration map in FIG. 5), and at the time of re-acceleration, it is possible to perform extremely good acceleration without a shortage of torque regardless of the number of passengers (weight).
[0057]
At this time, if the speed at the time of re-acceleration is, for example, the fourth speed, it is possible to jump from the fourth speed to the second speed in two steps at a time. Unlike the case of shifting gears, smooth acceleration with good response without shift shock can be realized.
In addition, after the shift stage is set to the second speed stage, when a large output torque is required continuously, the shift stage set to the second speed stage (optimal shift stage) based on the second fuzzy rule is continued well. Therefore, torqueful acceleration is sufficiently performed.
[0058]
In the above embodiment, when the vehicle load degree αVL is large and the accelerator opening VA and the accelerator opening change ΔVA are large, the optimum shift stage is set as shown in the consequent part of the first fuzzy rule R1. Although the second gear is used, the optimum gear, that is, the consequent part of the first fuzzy rule R1, may be set to, for example, “one or more gears lower than the target gear”. In this case, there is a problem whether it is necessary to make only one stage low speed or it is necessary to make two stages or more low speed stages, but this is related to the output of the conformity of the consequent part of the first fuzzy rule R1. What is necessary is just to determine according to a value. In this way, as shown in the above embodiment, the present invention is not limited to the case where re-acceleration is started at the fourth speed (A1 position in FIG. 5), for example. ), It is possible to achieve smooth acceleration without torque shortage even when re-acceleration is performed.
[0059]
Further, in the above embodiment, the fuzzy inference method is used, but without performing such fuzzy inference, it is determined whether or not the speed should be the second speed (optimal shift speed) by simply determining the threshold value. However, the same effect can be obtained.
In the above embodiment, the mechanical gear type transmission 4 is used as the automatic transmission. However, the present invention is not limited to this, and the transmission control device is a torque converter and a planet that are normally mounted on a passenger car. It is also possible to apply to an automatic transmission composed of gears.
[0060]
The change lever 60 is also provided with M (manual) ranges of 1st to 5th gears in addition to the N (neutral) range, R (reverse) range, and D (drive) range. Manual shifting as well as automatic shifting is possible. The change lever 60 switches the gear position by instructing the gear range up (+) and down (-) from the current gear position hold position instead of the first to fifth gear M ranges. It may be of the type that operates.
[0061]
【The invention's effect】
As described above in detail, according to the shift control device for a vehicle automatic transmission according to claim 1 of the present invention,While setting the target shift stage based on a preset shift map according to the vehicle speed and the operating state of the accelerator pedal,When the accelerator pedal transitions from the off state to the on state,Priority over target gearThe driver's intention to accelerate and the vehicle load statusFuzzy inference with inputAccording toMeticulousShift control can be performed at the optimum shift speed, and therefore, when the vehicle load is large, for example, when the vehicle weight (number of passengers, etc.) or gradient resistance is large, the driver's willingness to accelerate is greatly increased. In some cases, it becomes possible to generate a driving torque larger than that of the normal target shift speed, to prevent a shortage of torque of the vehicle, to realize torque-full reacceleration running, and to improve drivability.
[0062]
Further, in the present invention, even if the difference between the current shift speed and the optimum shift speed is two or more, the jumping is realized at a stretch, so that the shift is executed step by step step by step. There is no shift shock, and the shift can be achieved smoothly with good response. According to the shift control device for an automatic transmission for a vehicle according to claim 2, the magnitude of the intention to accelerate can be easily obtained from the accelerator opening and the accelerator opening change.The mostSuitable speed changeStepEasySet tobe able to.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a drive system of a vehicle to which a shift control device according to the present invention is applied.
FIG. 2 is a part of a flowchart showing a control routine of deceleration reacceleration control according to the present invention.
FIG. 3 is a remaining portion of the flowchart showing a control routine for deceleration reacceleration control following FIG. 2;
FIG. 4 is a control block diagram showing a shift control procedure.
FIG. 5 is a diagram showing a shift map (deceleration map and acceleration map) for setting a target gear position.
[Explanation of symbols]
1 Diesel engine
3 Clutch device
4 Transmission
8 Engine rotation sensor
68 Gear position sensor
70 Accelerator pedal
72 Accelerator opening sensor (accelerator operation state detection means)
78 Vehicle speed sensor (vehicle speed detection means)
80 Electronic control unit (ECU)
90 JudgmentPart
100 Vehicle load calculation unit(Load state detection means)
110 Target gear setting unit (target gear setting means)
120 Optimum gear position determination unit(Optimum gear position setting means)
130 gear stage control unit (gear stage control means)

Claims (2)

Vehicle speed detection means for detecting the vehicle speed;
An accelerator operation state detection means for detecting an operation state of the accelerator pedal;
Target gear setting means for setting a target gear based on the vehicle speed and the operation state of the accelerator pedal;
Acceleration intention detection means for detecting the driver's acceleration intention;
Load state detecting means for detecting the load state of the vehicle;
When the accelerator operation state detecting means detects that the accelerator pedal shifts from an off state to an on state, an optimum shift stage is set that sets an optimum shift stage based on at least the magnitude of the driver's intention to accelerate and the vehicle load state. Stage setting means;
Shift control is performed according to the target shift speed from the target shift speed setting means, and when the accelerator operation state detection means detects a shift from the off state to the on state of the accelerator pedal, the target shift speed is set. preferentially a shift speed control means for shifting control according to the optimum gear from the optimum gear setting means,
The target shift speed setting means sets the target shift speed based on a shift map set in advance according to the vehicle speed and the operation state of the accelerator pedal,
The optimum gear stage setting means sets the optimum gear stage based on at least fuzzy inference using the magnitude of the intention to accelerate and the vehicle load state as input parameters. . The accelerator operation state detection means detects accelerator opening and accelerator opening change,
2. The shift control apparatus for an automatic transmission for a vehicle according to claim 1, wherein the acceleration intention detecting means detects the magnitude of the acceleration intention according to the accelerator opening and the accelerator opening change.

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