JP4790254B2 - Mechanical transmission - Google Patents

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JP4790254B2
JP4790254B2 JP2004330164A JP2004330164A JP4790254B2 JP 4790254 B2 JP4790254 B2 JP 4790254B2 JP 2004330164 A JP2004330164 A JP 2004330164A JP 2004330164 A JP2004330164 A JP 2004330164A JP 4790254 B2 JP4790254 B2 JP 4790254B2
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明彦 渡辺
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Hino Motors Ltd
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Description

本発明は、機械式変速機に関するものである。   The present invention relates to a mechanical transmission.

従来より、車両用の変速機としては、変速操作を自動化した自動変速機が多く採用されている。   Conventionally, as a transmission for a vehicle, an automatic transmission in which a shift operation is automated has been widely used.

斯かる自動変速機としては、小型車両の場合、クラッチに代えてトルクコンバータを採用したものが主流になっているが、バスやトラック等の大型車両の場合、駆動トルクの伝達量が大きいため、トルクコンバータではその駆動トルクを充分に伝達することが困難となっていた。   As such an automatic transmission, in the case of a small vehicle, the one that adopts a torque converter instead of a clutch has become mainstream, but in the case of a large vehicle such as a bus or a truck, the amount of drive torque transmitted is large, In a torque converter, it has been difficult to sufficiently transmit the driving torque.

そこで、手動変速機(MT:Manual Transmission)に用いられるものと同様の機械式のクラッチを設けると共に、該クラッチを自動的に断接するアクチュエータを設け、これによりクラッチペダルを踏むことなく変速シフトを行えるようにした機械式自動変速機(AMT:Automated Manual Transmission)が大型車両用に開発されている。   Therefore, a mechanical clutch similar to that used in a manual transmission (MT) is provided, and an actuator that automatically connects and disconnects the clutch is provided, so that a shift shift can be performed without stepping on the clutch pedal. Such an automatic manual transmission (AMT) has been developed for large vehicles.

従来、大型車両に装備される機械式自動変速機のシフトレンジを切り換えるギアシフトユニットは、その変速操作におけるシフト操作力が大きいことから、主に圧縮空気で作動するエアシリンダ等が用いられていたが、近年においては、電動機による入力をパワーシフト手段により倍加して出力し変速機本体のシフト操作を行うようにしたものが提案されている。   Conventionally, a gear shift unit that switches the shift range of a mechanical automatic transmission installed in a large vehicle has a large shift operation force in the shift operation, and therefore, an air cylinder or the like that mainly operates with compressed air has been used. In recent years, it has been proposed that the input by the electric motor is doubled and output by the power shift means to shift the transmission main body.

図3はギアシフトユニットが設けられた機械式自動変速機の一例を示す斜視図であって、図中、1は図示していない制御部からの信号に応じて特定のギアを選択し、該選択したギアにより動力源からの入力を変速出力する変速機本体、2は変速機本体1のシフト操作を行うためのギアシフトユニットである。   FIG. 3 is a perspective view showing an example of a mechanical automatic transmission provided with a gear shift unit. In FIG. 3, reference numeral 1 designates a specific gear according to a signal from a control unit (not shown), and the selection is made. A transmission main body 2 that shifts and outputs an input from a power source by using the gear, and a gear shift unit 2 for performing a shift operation of the transmission main body 1.

前記ギアシフトユニット2は、直流モータ等の電動機3が一体に取り付けられた空圧サーボ式のパワーシフト手段4によって構成され、該パワーシフト手段4の出力ロッド5の先端部に、ストライカ6が出力ロッド5と直交する方向ヘ延びるよう突設され、該ストライカ6が、変速機本体1のシフト操作用のシフトアーム7に連結されている。   The gear shift unit 2 is constituted by a pneumatic servo type power shift means 4 to which an electric motor 3 such as a DC motor is integrally attached, and a striker 6 is connected to the tip of the output rod 5 of the power shift means 4. 5, the striker 6 is connected to a shift arm 7 for shifting operation of the transmission main body 1.

そして、前記変速機本体1のシフト操作を行う際には、前記電動機3によってパワーシフト手段4に内蔵されている図示していないボールネジを回転駆動し、該ボールネジに螺嵌されたナットをボールネジの軸線方向へ移動させつつ、該ナットに入力ロッドを介して接続された前記出力ロッド5を、圧縮空気圧を補助的に利用してその出力を倍加した状態で、伸縮させ、ストライカ6を介してシフトアーム7を駆動するようになっている。   When the shift operation of the transmission body 1 is performed, a ball screw (not shown) built in the power shift means 4 is rotationally driven by the electric motor 3, and a nut screwed into the ball screw is attached to the ball screw. While moving in the axial direction, the output rod 5 connected to the nut via an input rod is expanded and contracted in a state where the output is doubled by using compressed air pressure, and is shifted via a striker 6. The arm 7 is driven.

尚、前述の如き機械式自動変速機のギアシフトユニットの一般的技術水準を示すものとしては、例えば、特許文献1がある。
特開2003−314687号公報
For example, Patent Document 1 shows a general technical level of the gear shift unit of the mechanical automatic transmission as described above.
JP 2003-314687 A

ところで、従来の場合、変速機本体1のシフト操作時には、ギアシフトユニット2の電動機3に対して一定の電流を付与するようになっていたが、このようにギアシフトユニット2の電動機3に対して一定の電流を付与するのでは、応答性、出力荷重が充分に得られず、変速性能が目標とするレベルに達しなかった。   By the way, in the conventional case, a constant current is applied to the electric motor 3 of the gear shift unit 2 during the shift operation of the transmission main body 1. In this way, the electric motor 3 of the gear shift unit 2 is constant. In this case, the response and output load were not sufficiently obtained, and the speed change performance did not reach the target level.

尚、前述の如く、ギアシフトユニット2の電動機3に対して一定の電流を付与した場合に、充分な性能が得られないのは、パワーシフト手段4に内蔵されている図示していないピストン、スプリング等の傾きや引っ掛かりに伴う摺動抵抗に起因していると考えられる。   As described above, when a constant current is applied to the electric motor 3 of the gear shift unit 2, a sufficient performance cannot be obtained because the piston and spring (not shown) built in the power shift means 4 are not shown. This is thought to be due to the sliding resistance associated with the inclination and catching.

本発明は、斯かる実情に鑑み、応答性を向上し得、充分な出力荷重を得ることができ、且つギア入り完了までの同期時間も短縮し得る機械式変速機を提供しようとするものである。   In view of such circumstances, the present invention is intended to provide a mechanical transmission that can improve responsiveness, can obtain a sufficient output load, and can shorten the synchronization time until completion of gear engagement. is there.

本発明は、電動機による入力をパワーシフト手段により倍加して出力し変速機本体のシフト操作を行うようにしたギアシフトユニットを有する機械式変速機であって、
変速機本体のシフト操作開始時に、電動機に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止した後、所望の周波数で振動するディザー電流を所要時間だけ付与し、続いて一定の電流を付与することを特徴とする機械式変速機にかかるものである。
The present invention is a mechanical transmission having a gear shift unit that doubles and outputs an input by an electric motor by a power shift means to perform a shift operation of the transmission main body,
At the start of the shifting operation of the transmission body, a dither current that oscillates at a desired frequency is applied to the motor for the required time, and after the current application is stopped, the dither current that vibrates at the desired frequency is applied for the required time. The mechanical transmission is characterized in that it is applied and subsequently a constant current is applied.

前述の如く、変速機本体のシフト操作時に、電動機に対して所望の周波数で振動するディザー電流を付与すると、電動機のパワーシフト手段に対する入力が小刻みに振動して伝達されることから、パワーシフト手段の摺動部の静摩擦が動摩擦へと変わり、起動時の摩擦が低減されることにより、応答性が良くなると共に、パワーシフト手段に内蔵されているピストン、スプリング等の傾きや引っ掛かりに伴う摺動抵抗もキャンセルされ、出力荷重も充分に上がり、更に、ギア入りが完了するまでの同期時間も短くなる。又、変速機本体のシフト操作開始時に、電動機に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止した後、所望の周波数で振動するディザー電流を所要時間だけ付与し、続いて一定の電流を付与するようにしているため、電動機自体の起動時におけるイナーシャが打ち消される形となり、電動機の動きも滑らかとなる一方、ギア入り完了直前に出力荷重がハンチングを起こすことが避けられ、性能をより向上させることが可能となり、又、ギア入り完了までディザー電流を付与するのに比べ、電動機の寿命を延長させることも可能となる。尚、本明細書で一定電流とは、あえてディザーを与えることのない一定に制御した電流を意味するAs described above, when a dither current that vibrates at a desired frequency is applied to the motor during a shift operation of the transmission body, the input to the power shift means of the motor is vibrated and transmitted in small increments. The static friction of the sliding part of the motor is changed to dynamic friction, and the friction at the time of starting is reduced, so that the responsiveness is improved and the sliding due to the tilt or catching of the piston, spring etc. built in the power shift means The resistance is also canceled, the output load is sufficiently increased, and the synchronization time until the gear engagement is completed is shortened. Also, at the start of the shifting operation of the transmission body, a dither current that vibrates at a desired frequency is applied to the motor for a required time , and after the current application is stopped , the dither current that vibrates at the desired frequency is applied. Since only the required time is applied, and then a constant current is applied, the inertia at the start-up of the motor itself is canceled out, and the motor moves smoothly, while the output load is increased immediately before the completion of gear engagement. Hunting can be avoided and the performance can be further improved, and the life of the motor can be extended as compared with the case where the dither current is applied until the completion of gear engagement. In the present specification, the constant current means a current controlled to a constant without giving a dither .

本発明の機械式変速機によれば、応答性を向上し得、充分な出力荷重を得ることができ、且つギア入り完了までの同期時間も短縮し得るという優れた効果を奏し得る。   According to the mechanical transmission of the present invention, the responsiveness can be improved, a sufficient output load can be obtained, and the excellent effect of shortening the synchronization time until the completion of gear engagement can be obtained.

以下、本発明の実施の形態を添付図面を参照して説明する。   Embodiments of the present invention will be described below with reference to the accompanying drawings.

図1は本発明を実施する形態の参考例であって、図3に示す変速機本体1のシフト操作時に、電動機3に対して所望の周波数で振動するディザー電流を付与するようにしたものである。 FIG. 1 is a reference example of an embodiment of the present invention, in which a dither current that vibrates at a desired frequency is applied to the motor 3 during a shift operation of the transmission main body 1 shown in FIG. is there.

参考例の場合、変速機本体1のシフト操作開始時に、電動機3に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止した後、所望の周波数で振動するディザー電流をギア入り完了まで付与するようにしてある。 In the case of this reference example, when the shift operation of the transmission body 1 is started, a dither current that vibrates at a desired frequency is applied to the electric motor 3 for a required time, and once the current application is stopped, at a desired frequency. An oscillating dither current is applied until completion of gear engagement.

次に、上記参考例の作用を説明する。 Next, the operation of the reference example will be described.

前述の如く、変速機本体1のシフト操作時に、電動機3に対して所望の周波数で振動するディザー電流を付与すると、電動機3のパワーシフト手段4に対する入力が小刻みに振動して伝達されることから、パワーシフト手段4の摺動部の静摩擦が動摩擦へと変わり、起動時の摩擦が低減されることにより、応答性が良くなると共に、パワーシフト手段4に内蔵されている図示していないピストン、スプリング等の傾きや引っ掛かりに伴う摺動抵抗もキャンセルされ、出力荷重も充分に上がり、更に、ギア入りが完了するまでの同期時間も短くなる。   As described above, when a dither current that vibrates at a desired frequency is applied to the motor 3 during a shift operation of the transmission body 1, the input to the power shift means 4 of the motor 3 is vibrated and transmitted in small increments. The static friction of the sliding portion of the power shift means 4 is changed to dynamic friction, and the friction at the time of starting is reduced, so that the response is improved and the piston (not shown) built in the power shift means 4 is provided. The sliding resistance associated with the inclination and catching of the spring is also canceled, the output load is sufficiently increased, and the synchronization time until the gear engagement is completed is shortened.

尚、図1中、入力電流は細線で示し、出力荷重は太い実線で示してあるが、ギアシフトユニット2の電動機3に対して一定の電流を付与した場合の仮想線で示す出力荷重と比較し、応答性が良く、出力荷重が高く、ギア入りが完了するまでの同期時間も短くなっていることがわかる。   In FIG. 1, the input current is indicated by a thin line and the output load is indicated by a thick solid line, but compared with the output load indicated by an imaginary line when a constant current is applied to the motor 3 of the gear shift unit 2. It can be seen that the responsiveness is good, the output load is high, and the synchronization time until the gear engagement is completed is shortened.

又、変速機本体1のシフト操作開始時に、電動機3に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止すると、電動機3自体の起動時におけるイナーシャが打ち消される形となり、電動機3の動きも滑らかとなる。   Further, when the shift operation of the transmission main body 1 is started, a dither current that vibrates at a desired frequency is applied to the motor 3 for a required time, and once the current application is stopped, the inertia at the start-up of the motor 3 itself is reduced. The form is canceled out and the movement of the electric motor 3 becomes smooth.

こうして、応答性を向上し得、充分な出力荷重を得ることができ、且つギア入り完了までの同期時間も短縮し得る。   Thus, the responsiveness can be improved, a sufficient output load can be obtained, and the synchronization time until the completion of gear engagement can be shortened.

但し、図1に示す如く、電動機3に対して所望の周波数で振動するディザー電流をギア入り完了まで付与すると、ディザー電流による振動が変速機本体1のシンクロメッシュ機構に伝播し、同期完了後のかき分け時にボーク条件が崩れ、シンクロナイザリングとギアコーンとの間で回転差が生じてハンチング(ギアが入ったり抜けたりするギア鳴き現象)が発生することがある。又、ディザー電流を長い時間与えることは、電動機3の寿命を短くしてしまう可能性もある。   However, as shown in FIG. 1, when a dither current that vibrates at a desired frequency is applied to the electric motor 3 until the completion of gear engagement, the vibration due to the dither current propagates to the synchromesh mechanism of the transmission body 1, and after the synchronization is completed. Bokeh conditions may be disrupted when scraping, and a difference in rotation may occur between the synchronizer ring and the gear cone, resulting in hunting (gearing phenomenon in which gears come in and out). Further, giving the dither current for a long time may shorten the life of the motor 3.

そこで、図2に示す如く、変速機本体1のシフト操作開始時に、電動機3に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止した後、所望の周波数で振動するディザー電流を所要時間だけ付与し、続いて一定の電流を付与することが有効となる。   Therefore, as shown in FIG. 2, when the shift operation of the transmission main body 1 is started, a dither current that vibrates at a desired frequency is applied to the electric motor 3 for a required time. It is effective to apply a dither current that oscillates at a frequency for a required time, and then apply a constant current.

このようにすると、電動機3自体の起動時におけるイナーシャが打ち消される形となり、電動機3の動きが滑らかとなる一方、ギア入り完了直前に出力荷重がハンチングを起こすことが避けられ、性能をより向上させることが可能となり、又、ギア入り完了までディザー電流を付与するのに比べ、電動機3の寿命を延長させることも可能となる。   In this way, the inertia at the start of the motor 3 itself is canceled out, and the movement of the motor 3 becomes smooth, while the output load is prevented from hunting immediately before the completion of gear engagement, and the performance is further improved. In addition, it is possible to extend the life of the electric motor 3 as compared with the case where the dither current is applied until the gear engagement is completed.

尚、本発明の機械式変速機は、上述の図示例にのみ限定されるものではなく、本発明の要旨を逸脱しない範囲内において種々変更を加え得ることは勿論である。   It should be noted that the mechanical transmission of the present invention is not limited to the illustrated example described above, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

本発明を実施する形態の参考例を示す線図であって、入力電流と出力荷重との関係を示す線図である。It is a diagram which shows the reference example of embodiment which implements this invention, Comprising: It is a diagram which shows the relationship between an input electric current and an output load. 本発明を実施する形態の例を示す線図であって、入力電流と出力荷重との関係を示す線図である。It is a diagram which shows an example of the form which implements this invention, Comprising: It is a diagram which shows the relationship between an input electric current and an output load. ギアシフトユニットが設けられた機械式自動変速機の一例を示す斜視図である。It is a perspective view which shows an example of the mechanical automatic transmission provided with the gear shift unit.

符号の説明Explanation of symbols

1 変速機本体
2 ギアシフトユニット
3 電動機
4 パワーシフト手段
5 出力ロッド
6 ストライカ
7 シフトアーム
DESCRIPTION OF SYMBOLS 1 Transmission body 2 Gear shift unit 3 Electric motor 4 Power shift means 5 Output rod 6 Striker 7 Shift arm

Claims (1)

電動機による入力をパワーシフト手段により倍加して出力し変速機本体のシフト操作を行うようにしたギアシフトユニットを有する機械式変速機であって、
変速機本体のシフト操作開始時に、電動機に対して、所望の周波数で振動するディザー電流を所要時間だけ付与し、一旦電流の付与を停止した後、所望の周波数で振動するディザー電流を所要時間だけ付与し、続いて一定の電流を付与することを特徴とする機械式変速機。
A mechanical transmission having a gear shift unit that doubles and outputs an input by an electric motor by a power shift means to perform a shift operation of the transmission body,
At the start of the shifting operation of the transmission body, a dither current that oscillates at a desired frequency is applied to the motor for the required time, and after the current application is stopped, the dither current that vibrates at the desired frequency is applied for the required time. A mechanical transmission characterized in that a constant current is applied .
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JP4609418B2 (en) 2006-11-15 2011-01-12 トヨタ自動車株式会社 Control device and control method for shift switching mechanism
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US6358183B1 (en) * 2000-04-27 2002-03-19 Eaton Corporation System/method for lever shifting of a controller-assisted, manually shifted transmission
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