JP2016223468A

JP2016223468A - Continuously variable transmission

Info

Publication number: JP2016223468A
Application number: JP2015107536A
Authority: JP
Inventors: 慎山本; Shin Yamamoto
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2015-05-27
Filing date: 2015-05-27
Publication date: 2016-12-28
Anticipated expiration: 2035-05-27
Also published as: JP6558075B2

Abstract

PROBLEM TO BE SOLVED: To obtain a structure which can start power transmission without generating an excess slide at a traction part of a toroidal-type continuously variable transmission immediately after a start of an operation even in an extremely-low temperature environment while securing the transmission efficiency of the toroidal-type continuously variable transmission.SOLUTION: A gear change ratio of a toroidal-type continuously variable transmission 21 is made to coincide with a mode switching point being a gear change ratio at the switching of a low-speed mode and a high-speed mode, a low-speed clutch 7 and a high-speed clutch 8 are simultaneously connected, and in a state that an output-side clutch mechanism 24 is disconnected, a drive source is started.SELECTED DRAWING: Figure 1

Description

この発明は、例えば車両（自動車）用、建設機械用、航空機等で使用される発電機用、ポンプ等の各種産業機械用の自動変速装置等として利用する、トロイダル型無段変速機を組み込んだ無段変速装置の改良に関する。 The present invention incorporates a toroidal continuously variable transmission used as an automatic transmission for various industrial machines such as a vehicle (automobile), a construction machine, a generator used in an aircraft, a pump, and the like. The present invention relates to an improvement of a continuously variable transmission.

自動車用変速機としてトロイダル型無段変速機を使用する事が、従来から広く知られ、一部で実施されている。又、例えば特許文献１には、航空機等の発電機を一定の回転速度で回転駆動する為に、トロイダル型無段変速機を使用する事が記載されている。又、変速比の変動幅をより大きくすべく、トロイダル型無段変速機と遊星歯車式変速機とを組み合わせた無段変速装置も、特許文献２に記載される等により従来から広く知られている。又、例えば特許文献３には、所謂ギヤードニュートラルと呼ばれ、入力部材を一方向に回転させたまま、出力部材の回転状態を、停止状態を挟んで正転、逆転に切り換えられる無段変速装置が記載されている。前記特許文献３に記載された無段変速装置は、クラッチ装置（低速用クラッチ及び高速用クラッチ）の断接を制御する事により、変速状態を、ギヤードニュートラル状態（変速比無限大の状態）を実現する低速モードと、この低速モードと比べて前記入力部材と前記出力部材との間の減速比が小さい高速モードとの何れかのモードで運転する。 The use of a toroidal-type continuously variable transmission as an automobile transmission has been widely known and practiced in part. Further, for example, Patent Document 1 describes that a toroidal continuously variable transmission is used in order to rotationally drive a generator such as an aircraft at a constant rotational speed. A continuously variable transmission that combines a toroidal type continuously variable transmission and a planetary gear type transmission in order to further increase the fluctuation range of the gear ratio has been widely known as described in Patent Document 2 and the like. Yes. Further, for example, in Patent Document 3, a so-called geared neutral is a continuously variable transmission that can switch the rotation state of the output member between forward rotation and reverse rotation with the input member rotated in one direction with the stop state interposed therebetween. Is described. The continuously variable transmission described in Patent Document 3 controls the shift state of the clutch device (the low speed clutch and the high speed clutch), thereby changing the gear shift state to the geared neutral state (the state where the gear ratio is infinite). The operation is performed in any one of a low speed mode to be realized and a high speed mode in which a reduction ratio between the input member and the output member is smaller than that in the low speed mode.

図４は、前記各特許文献に記載される等して従来から知られているトロイダル型無段変速機の第１例を示している。このトロイダル型無段変速機は、入力回転軸１の両端寄り部分の周囲に１対の入力側ディスク２ａ、２ｂを、それぞれがトロイド曲面である内側面同士を互いに対向させた状態で、ボールスプライン１８、１８を介して支持し、遠近動可能に、且つ、前記入力回転軸１と同期して回転する様にしている。又、この入力回転軸１の中間部周囲に出力筒３を、この入力回転軸１に対する相対回転を可能に支持している。又、この出力筒３の外周面には、軸方向中央部に出力歯車４を固設すると共に、軸方向両端部に１対の出力側ディスク５、５を、スプライン係合により、前記出力筒３と同期した回転を可能に支持している。又、この状態で、それぞれがトロイド曲面である、前記両出力側ディスク５、５の内側面を、前記両入力側ディスク２ａ、２ｂの内側面に対向させている。 FIG. 4 shows a first example of a toroidal-type continuously variable transmission that has been conventionally known as described in each of the above patent documents. This toroidal-type continuously variable transmission has a pair of input-side disks 2a and 2b around the portions near both ends of the input rotary shaft 1, and a ball spline in a state where the inner side surfaces, each of which is a toroidal curved surface, face each other. 18, 18 is supported so as to be able to move far and away, and to rotate in synchronization with the input rotary shaft 1. An output cylinder 3 is supported around the intermediate portion of the input rotary shaft 1 so as to be able to rotate relative to the input rotary shaft 1. Further, on the outer peripheral surface of the output cylinder 3, an output gear 4 is fixed at the center in the axial direction, and a pair of output side disks 5, 5 are connected to both ends in the axial direction by spline engagement. The rotation synchronized with 3 is supported. In this state, the inner side surfaces of the output side disks 5 and 5, each of which is a toroidal curved surface, are opposed to the inner side surfaces of the input side disks 2 a and 2 b.

又、前記両入力側ディスク２ａ、２ｂと前記両出力側ディスク５、５との間に、それぞれの周面を球状凸面とした複数個のパワーローラ６、６を挟持している。これら各パワーローラ６、６は、それぞれトラニオン７、７に回転自在に支持されており、前記両入力側ディスク２ａ、２ｂの回転に伴って回転しつつ、これら両入力側ディスク２ａ、２ｂから前記両出力側ディスク５、５に動力を伝達する。即ち、トロイダル型無段変速機の運転時には、駆動軸８により一方（図４の左方）の入力側ディスク２ａを、押圧装置９（図示の構造はローディングカム式の押圧装置）を介して回転駆動する。この結果、前記入力回転軸１の両端部に支持された１対の入力側ディスク２ａ、２ｂが、互いに近づく方向に押圧されつつ同期して回転する。そして、この回転が、前記各パワーローラ６、６を介して前記両出力側ディスク５、５に伝わり、前記出力歯車４から取り出される。 Further, a plurality of power rollers 6 and 6 each having a spherical convex surface are sandwiched between the input disks 2 a and 2 b and the output disks 5 and 5. The power rollers 6 and 6 are rotatably supported by the trunnions 7 and 7, respectively, and rotate with the rotation of the two input side disks 2a and 2b. Power is transmitted to both output side disks 5 and 5. That is, during operation of the toroidal-type continuously variable transmission, one (left side in FIG. 4) input side disk 2a is rotated by a drive shaft 8 via a pressing device 9 (the structure shown is a loading cam type pressing device). To drive. As a result, the pair of input-side disks 2a and 2b supported at both ends of the input rotation shaft 1 rotate synchronously while being pressed in a direction approaching each other. Then, this rotation is transmitted to the output side disks 5 and 5 through the power rollers 6 and 6 and is taken out from the output gear 4.

又、前記入力回転軸１の両端部近傍で前記両入力側ディスク２ａ、２ｂを軸方向両側から挟む位置に、それぞれ予圧ばね１０ａ、１０ｂを設けている。そして、前記押圧装置９の非作動時（前記駆動軸８の停止時）にも、前記各パワーローラ６、６の周面と、前記入力側、出力側各ディスク２ａ、２ｂ、５の内側面との転がり接触部（トラクション部）の面圧を、必要最低限だけは確保する様にしている。従って、これら各転がり接触部は、トロイダル型無段変速機の運転開始直後から、過大な滑りを生じる事なく、動力伝達を開始する。尚、前記必要最低限の面圧を確保する為の弾力は、前記押圧装置９の内径側に配置した予圧ばね１０ａにより得る。前記入力回転軸１の先端部に螺着したローディングナット１１と入力側ディスク２ｂの外側面との間に配置した予圧ばね１０ｂは、前記押圧装置９の急な作動時に加わる衝撃を緩和するものであって、省略する事もできる。設ける場合には、十分に（大きなトルクを伝達する際にも完全に押し潰されない程度に）大きな弾力を持たせる。 Further, preload springs 10a and 10b are provided at positions where both the input side disks 2a and 2b are sandwiched from both sides in the axial direction in the vicinity of both ends of the input rotary shaft 1, respectively. Even when the pressing device 9 is not in operation (when the drive shaft 8 is stopped), the peripheral surfaces of the power rollers 6 and 6 and the inner surfaces of the input side and output side disks 2a, 2b and 5 are provided. The surface pressure of the rolling contact part (traction part) is secured to the minimum necessary. Therefore, these rolling contact portions start power transmission without causing excessive slip immediately after the start of operation of the toroidal continuously variable transmission. The elasticity for securing the minimum necessary surface pressure is obtained by a preload spring 10 a disposed on the inner diameter side of the pressing device 9. The preload spring 10b disposed between the loading nut 11 screwed to the tip end of the input rotary shaft 1 and the outer surface of the input side disk 2b alleviates the impact applied when the pressing device 9 is suddenly operated. It can be omitted. When it is provided, it has a sufficiently large elasticity (so as not to be completely crushed even when a large torque is transmitted).

又、特許文献４には、ローディングナットに代えてコッタと呼ばれる係止環を用いて、入力側ディスク（押圧装置を設けた側と反対側の入力側ディスク）を支持する構造が記載されている。図５は、この様な係止環を組み込んだ従来構造の第２例を示している。この従来構造の第２例の場合、入力側ディスク２ｂの中心部にスプライン孔１２を形成し、このスプライン孔１２と、入力回転軸１ａの先端寄り部分の外周面に形成したスプライン軸部１３とを係合している。又、この入力回転軸１ａの先端部外周面で、このスプライン軸部１３から軸方向に外れた部分に、全周に亙って係止溝１４を形成し、この係止溝１４に、複数（２〜４個）の部分円弧状の素子から成る係止環１５の径方向内半部を係止している。そして、この係止環１５の内側面（図５の左側面）のうちの径方向外端寄り部分を、入力側ディスク２ｂの外側面のうちの径方向内端部に当接させる。油圧式の押圧装置９ａの非作動時に、各パワーローラ６、６（図４参照）の周面と、入力、出力側各ディスク２ａ、２ｂ、５ａの内側面との転がり接触部の面圧を必要最低限確保する為の、予圧ばね１０ａの弾力の調整は、前記係止環１５として、適正な軸方向の厚さ寸法を有するものを選択する事により図る。又、前記入力回転軸１ａの先端部に断面Ｌ字形の抑え環１６を外嵌し、この抑え環１６の内周面を、前記係止環１５の外周面に当接或いは近接対向させる事により、この係止環１５（を構成する各素子）が前記係止溝１４から抜け出るのを防止している。この様な抑え環１６は、前記入力回転軸１ａの先端部に係止した止め輪１７により軸方向の変位を阻止する。以上の様な構成により、前記入力側ディスク２ｂを前記入力回転軸１ａに、この入力回転軸１ａと同期した回転を可能に支持している。尚、前記従来構造の第２例の場合、出力側ディスク５ａとして一体型のものを使用する事により、トロイダル型無段変速機全体として小型・軽量化を図っている。但し、この部分の構造及び作用に就いては、本発明の要旨とは関係しない為、詳しい説明は省略する。 Further, Patent Document 4 describes a structure for supporting an input side disk (an input side disk opposite to the side where the pressing device is provided) using a locking ring called a cotter instead of a loading nut. . FIG. 5 shows a second example of a conventional structure incorporating such a locking ring. In the case of the second example of this conventional structure, a spline hole 12 is formed at the center of the input side disk 2b, and the spline hole 12 and a spline shaft portion 13 formed on the outer peripheral surface of the input rotary shaft 1a. Is engaged. In addition, a locking groove 14 is formed over the entire circumference on the outer peripheral surface of the tip end portion of the input rotary shaft 1a at a portion that is axially removed from the spline shaft portion 13, and a plurality of locking grooves 14 are formed in the locking groove 14. The radially inner half of the locking ring 15 made up of (2 to 4) partial arc-shaped elements is locked. Then, the radially outer end portion of the inner side surface (left side surface in FIG. 5) of the locking ring 15 is brought into contact with the radially inner end portion of the outer side surface of the input side disk 2b. When the hydraulic pressing device 9a is not operated, the surface pressure of the rolling contact portion between the peripheral surface of each power roller 6, 6 (see FIG. 4) and the inner surface of each of the input and output side disks 2a, 2b, 5a is measured. The adjustment of the elasticity of the preload spring 10a to ensure the necessary minimum is achieved by selecting the locking ring 15 having an appropriate axial thickness dimension. Further, a retaining ring 16 having an L-shaped cross section is fitted on the tip of the input rotating shaft 1a, and the inner peripheral surface of the retaining ring 16 is brought into contact with or in close proximity to the outer peripheral surface of the locking ring 15. The locking ring 15 (elements constituting the locking ring 15) is prevented from coming out of the locking groove 14. Such a retaining ring 16 prevents axial displacement by a retaining ring 17 that is engaged with the tip of the input rotary shaft 1a. With the configuration described above, the input disk 2b is supported on the input rotary shaft 1a so as to be able to rotate in synchronization with the input rotary shaft 1a. In the case of the second example of the conventional structure, the entire toroidal continuously variable transmission is reduced in size and weight by using an integral output side disk 5a. However, since the structure and operation of this portion are not related to the gist of the present invention, detailed description thereof is omitted.

上述の様な従来構造の第１例及び第２例の何れの構造の場合でも、トロイダル型無段変速機を通過するトルクが小さい場合のこのトロイダル型無段変速機の伝達効率を確保しつつ、極低温環境下においても、このトロイダル型無段変速機の運転開始直後からトラクション部で過大な滑りを生じる事なく、動力伝達を開始する為には、更なる改良の余地がある。即ち、前記トロイダル型無段変速機を通過するトルクが小さい場合には、前記各トラクション部で過大な滑りを生じる事なく、トルクの伝達を行う為に必要な、これら各トラクション部の面圧（これら各トラクション部の為の押圧装置が発生すべき押圧力）は小さい。この為、この押圧装置の非作動時に、これら各トラクション部の面圧を必要最低限確保する為の予圧ばねの弾力が大きいと、前記トロイダル型無段変速機を通過するトルクが小さい場合に、前記各トラクション部の面圧が過大になり、これら各トラクション部で発生する、スピンロスを始めとする伝達ロスが大きくなり、前記トロイダル型無段変速機の伝達効率が低下する。これに対し、極低温環境下（例えば−４０℃以下）では、前記各トラクション部に存在する（トラクション部を潤滑する）トラクションオイルのトラクション係数μ_ｔ（＝接線力／法線力）が小さくなる。この為、極低温環境下では、前記トロイダル型無段変速機の運転開始に伴い、前記押圧装置の発生する押圧力、延いては、前記各トラクション部の面圧が上昇する事により上昇する、これら各トラクション部で伝達可能なトルクの上昇量が、前記トラクションオイルの温度が高い（常温である）場合に比べて、小さくなる。従って、極低温環境下で、前記トロイダル型無段変速機の運転開始直後から前記各トラクション部で過大な滑りを生じる事なく、動力伝達を開始する為には、前記予圧ばねの弾力をある程度以上確保する必要がある。 In any of the first and second examples of the conventional structure as described above, the transmission efficiency of the toroidal continuously variable transmission when the torque passing through the toroidal continuously variable transmission is small is ensured. Even in a cryogenic environment, there is room for further improvement in order to start power transmission without causing excessive slippage in the traction portion immediately after the start of operation of the toroidal type continuously variable transmission. That is, when the torque passing through the toroidal-type continuously variable transmission is small, the surface pressure of each of these traction parts (in order to transmit the torque without causing excessive slip in each of the traction parts ( The pressing force to be generated by the pressing device for each of these traction sections is small. For this reason, when the elasticity of the preload spring for ensuring the necessary minimum surface pressure of each traction portion is large when the pressing device is not in operation, when the torque passing through the toroidal continuously variable transmission is small, The surface pressure of each of the traction parts becomes excessive, the transmission loss such as spin loss generated in each of these traction parts increases, and the transmission efficiency of the toroidal continuously variable transmission decreases. On the other hand, in an extremely low temperature environment (for example, −40 ° C. or lower), the traction coefficient μ _t (= tangential force / normal force) of the traction oil existing in each traction part (lubricating the traction part) becomes small. . For this reason, in a cryogenic environment, with the start of operation of the toroidal type continuously variable transmission, the pressing force generated by the pressing device, and consequently the surface pressure of each traction portion increases. The amount of increase in torque that can be transmitted by each of these traction units is smaller than when the temperature of the traction oil is high (normal temperature). Therefore, in order to start power transmission without causing excessive slippage in each traction part immediately after the start of operation of the toroidal type continuously variable transmission in a cryogenic environment, the elasticity of the preload spring is more than a certain degree. It is necessary to secure.

特開２００１−１５８４００号公報JP 2001-158400 A 特開平１１−６３１４６号公報JP 11-63146 A 特開２００２−１３９１２４号公報JP 2002-139124 A 特開２０００−２０５３６１号公報JP 2000-205361 A

本発明は、上述の様な事情に鑑み、トロイダル型無段変速機の伝達効率を確保しつつ、極低温環境下においても、運転開始直後からこのトロイダル型無段変速機のトラクション部で過大な滑りを生じる事なく、動力伝達を開始できる無段変速装置の構造を実現する事を目的としている。 In view of the circumstances as described above, the present invention ensures that the transmission efficiency of the toroidal continuously variable transmission is ensured, and even in a cryogenic environment, the traction portion of the toroidal continuously variable transmission is excessively large immediately after the start of operation. The object is to realize a structure of a continuously variable transmission that can start power transmission without causing slippage.

本発明の無段変速装置は、エンジン等の駆動源により一方向に回転駆動される入力部材と、発電機の回転子（ロータ）やデファレンシャルギヤの入力部等の被駆動部を回転駆動する為の出力部材と、トロイダル型無段変速機と、複数の歯車を組み合わせて成る歯車式の差動機構と、これらトロイダル型無段変速機と差動機構との動力の伝達状態を切り換える為のクラッチ装置とを備える。
このうちのクラッチ装置は、低速用クラッチと、高速用クラッチとから構成される。
この低速用クラッチは、前記入力部材と前記出力部材との間の減速比が大きい低速モードを実現する際に接続され、同じく減速比が小さい高速モードを実現する際に接続を断たれるものである。
前記高速用クラッチは、前記高速モードを実現する際に接続され、前記低速モードを実現する際に接続を断たれるものである。 The continuously variable transmission of the present invention rotationally drives an input member that is driven to rotate in one direction by a drive source such as an engine and a driven part such as a generator rotor or a differential gear input part. Output member, toroidal continuously variable transmission, gear-type differential mechanism formed by combining a plurality of gears, and a clutch for switching the power transmission state between these toroidal-type continuously variable transmission and the differential mechanism Device.
Of these, the clutch device includes a low speed clutch and a high speed clutch.
This low speed clutch is connected when realizing a low speed mode in which the reduction ratio between the input member and the output member is large, and is disconnected when realizing a high speed mode in which the reduction ratio is also small. is there.
The high speed clutch is connected when the high speed mode is realized, and is disconnected when the low speed mode is realized.

特に本発明の無段変速装置においては、前記トロイダル型無段変速機の変速比を、前記低速モードと前記高速モードとを切り換える際の変速比（モード切換ポイント、ＭＣ値）に一致させると共に、前記低速用、高速用両クラッチを同時に接続した状態で、前記駆動源を始動する。 In particular, in the continuously variable transmission of the present invention, the transmission ratio of the toroidal type continuously variable transmission is matched with the transmission ratio (mode switching point, MC value) when switching between the low speed mode and the high speed mode, The drive source is started in a state where both the low speed and high speed clutches are simultaneously connected.

上述の様な本発明の無段変速装置に組み込まれるトロイダル型無段変速機は、入力側ディスクと、出力側ディスクと、複数個のパワーローラと、押圧装置とを備える。
このうちの入力側ディスクは、前記差動機構の第一の入力部と共に前記入力部材により回転駆動される。
前記出力側ディスクは、前記入力側ディスクと同心に、且つ、この入力側ディスクに対する相対回転を自在として支持され、前記差動機構の第二の入力部に動力の伝達を可能に接続される。
前記各パワーローラは、前記入力側ディスクと前記出力側ディスクとの間に挟持されて、これら入力側ディスクと出力側ディスクとの間で動力を伝達する。
前記押圧装置は、前記各パワーローラの周面と、前記入力側ディスク及び出力側ディスクの側面との転がり接触部であるトラクション部の面圧を確保する為、これら入力側ディスクと出力側ディスクとを互いに近づく方向に押圧するものである。この様な押圧装置としては、ローディングカム式或いは油圧式の押圧装置を使用する事ができる。
上述の様なトロイダル型無段変速機は、前記各パワーローラを、前記入力側ディスク及び前記出力側ディスクの中心軸に対し捩れの位置に存在する枢軸を中心に揺動させて、これら入力側ディスクと出力側ディスクとの間の変速比（トロイダル型無段変速機の変速比）を変える。
又、この様なトロイダル型無段変速機は、必要に応じて、予圧ばねを更に備える。この予圧ばねは、前記各トラクション部で、このトロイダル型無段変速機の運転開始（駆動源の始動）直後から、過大な滑りを生じる事なく、動力伝達を開始できる様にする為のもので、前記入力側ディスクと前記出力側ディスクとを互いに近づける方向の弾力を有する。この様な予圧ばねとして、例えば皿ばねを使用する事ができる。 The toroidal continuously variable transmission incorporated in the continuously variable transmission of the present invention as described above includes an input side disk, an output side disk, a plurality of power rollers, and a pressing device.
Of these, the input side disk is rotationally driven by the input member together with the first input portion of the differential mechanism.
The output-side disk is supported concentrically with the input-side disk and so as to be rotatable relative to the input-side disk, and is connected to the second input portion of the differential mechanism so as to be able to transmit power.
Each power roller is sandwiched between the input side disk and the output side disk, and transmits power between the input side disk and the output side disk.
The pressing device secures the surface pressure of the traction portion which is a rolling contact portion between the peripheral surface of each power roller and the side surfaces of the input side disk and the output side disk. Are pressed in a direction approaching each other. As such a pressing device, a loading cam type or a hydraulic pressing device can be used.
In the toroidal continuously variable transmission as described above, each of the power rollers is swung around a pivot that exists at a twisted position with respect to the central axis of the input side disk and the output side disk. The gear ratio between the disc and the output side disc (the gear ratio of the toroidal continuously variable transmission) is changed.
Moreover, such a toroidal continuously variable transmission further includes a preload spring as necessary. This preload spring is for enabling each traction section to start power transmission without causing excessive slip immediately after the start of operation of the toroidal continuously variable transmission (start of the drive source). The input side disc and the output side disc have elasticity in a direction to bring them close to each other. As such a preload spring, for example, a disc spring can be used.

上述の様な本発明の無段変速装置を実施する場合に好ましくは、前記出力部材と前記被駆動部との間に、これら出力部材と被駆動部との間の動力伝達の断接状態を切り換える為の出力側クラッチ機構を設ける。 Preferably, when the continuously variable transmission of the present invention as described above is implemented, a power transmission / reception state between the output member and the driven portion is preferably established between the output member and the driven portion. An output side clutch mechanism for switching is provided.

上述の様な本発明の無段変速装置によれば、トロイダル型無段変速機の伝達効率を確保しつつ、極低温環境下においても、運転開始直後からこのトロイダル型無段変速機のトラクション部で過大な滑りを生じる事なく、動力伝達を開始する事ができる。
即ち、本発明の場合、前記トロイダル型無段変速機の変速比をモード切換ポイントに一致させると共に、低速用、高速用両クラッチを同時に接続した状態で、駆動源を始動する様にしている為、この駆動源の始動時（トロイダル型無段変速機の運転開始直後）に、このトロイダル型無段変速機を通過するトルクを小さくする（理想的には、トロイダル型無段変速機を通過するトルクを０にする）事ができる。この為、押圧装置の非作動時にも、前記トロイダル型無段変速機のトラクション部の面圧を必要最低限確保する為の予圧ばねの弾力を小さく抑える事ができる（理想的には予圧ばねを省略できる）。従って、前記トロイダル型無段変速機を通過するトルクが小さい場合に、前記各トラクション部の面圧が過大になる事を防止して、前記トロイダル型無段変速機の伝達効率を確保する事ができる。又、トラクションオイルのトラクション係数が小さくなる、極低温環境下においても、前記トロイダル型無段変速機の運転開始直後から前記各トラクション部で過大な滑りを生じる事なく、動力伝達を開始する事ができる。 According to the continuously variable transmission of the present invention as described above, the traction section of the toroidal continuously variable transmission is started immediately after the start of operation even in a cryogenic environment while ensuring the transmission efficiency of the toroidal continuously variable transmission. Power transmission can be started without causing excessive slip.
In other words, in the present invention, the gear ratio of the toroidal-type continuously variable transmission is matched with the mode switching point, and the drive source is started with both the low speed clutch and the high speed clutch connected simultaneously. When starting this drive source (immediately after the start of operation of the toroidal continuously variable transmission), the torque passing through the toroidal continuously variable transmission is reduced (ideally, passing through the toroidal continuously variable transmission). Torque can be reduced to 0). For this reason, even when the pressing device is not in operation, the elasticity of the preload spring for ensuring the necessary minimum surface pressure of the traction portion of the toroidal continuously variable transmission can be kept small (ideally, the preload spring is Can be omitted). Therefore, when the torque passing through the toroidal continuously variable transmission is small, it is possible to prevent the surface pressure of each traction section from becoming excessive and to ensure the transmission efficiency of the toroidal continuously variable transmission. it can. Also, even in an extremely low temperature environment where the traction coefficient of the traction oil becomes small, power transmission can be started without causing excessive slippage in each traction section immediately after the start of operation of the toroidal continuously variable transmission. it can.

本発明の実施の形態の第１例を示す略断面図。1 is a schematic cross-sectional view showing a first example of an embodiment of the present invention. トロイダル型無段変速機の変速比と無段変速装置全体としての速度比との関係の１例を示す線図。The diagram which shows one example of the relationship between the gear ratio of a toroidal type continuously variable transmission, and the speed ratio as the whole continuously variable transmission. 本発明の実施の形態の第２例を示す略断面図。FIG. 6 is a schematic cross-sectional view showing a second example of an embodiment of the present invention. トロイダル型無段変速機の従来構造の第１例を示す断面図。Sectional drawing which shows the 1st example of the conventional structure of a toroidal type continuously variable transmission. 同じく第２例を示す断面図。Sectional drawing which similarly shows the 2nd example.

［実施の形態の第１例］
図１〜２は、本発明の実施の形態の第１例を示している。本例の無段変速装置は、図示しないエンジン等の駆動源により一方向に回転駆動される、入力部材である駆動軸８ａと、被駆動部であるデファレンシャルギヤ１９の入力部を回転駆動する為の出力部材である、中空状の出力軸２０と、トロイダル型無段変速機２１と、差動機構である遊星歯車式変速機２２と、これらトロイダル型無段変速機２１と遊星歯車式変速機２２との動力の伝達状態を切り換える為のクラッチ装置２３と、出力側クラッチ機構２４とを備える。 [First example of embodiment]
1 and 2 show a first example of an embodiment of the present invention. The continuously variable transmission of this example is configured to rotationally drive a drive shaft 8a as an input member and an input portion of a differential gear 19 as a driven portion, which are rotationally driven in one direction by a driving source such as an engine (not shown). A hollow output shaft 20, a toroidal-type continuously variable transmission 21, a planetary gear-type transmission 22 as a differential mechanism, and these toroidal-type continuously variable transmission 21 and planetary gear-type transmission. A clutch device 23 for switching the transmission state of power with the motor 22, and an output side clutch mechanism 24.

このうちのトロイダル型無段変速機２１は、１対の入力側ディスク２ａ、２ｂと、出力側ディスク５ａと、複数個のパワーローラ６、６と、複数個のトラニオン７、７（図４参照）と、押圧装置９ｂと、予圧ばね１０ａ（図４〜５参照）とを備える。このうちの入力側ディスク２ａ、２ｂは、前記駆動軸８ａと同軸に設けられた入力側回転軸１ｂの両端寄り部分に、それぞれがトロイド曲面である内側面同士を互いに対向させた状態で、遠近動可能に、且つ、前記入力側回転軸１ｂと同期した回転を可能に支持している。前記出力側ディスク５ａは、この入力側回転軸１ｂの軸方向に関して、前記両入力側ディスク２ａ、２ｂ同士の間位置に、それぞれがトロイド曲面である両側面をこれら両入力側ディスク２ａ、２ｂの内側面に対向させた状態で、これら両入力側ディスク２ａ、２ｂと同軸に、且つ、これら両入力側ディスク２ａ、２ｂに対する相対回転を可能に支持している。尚、出力側ディスクを、前述の図４に示す様な１対の素子を結合して成るものとする事もできる。 Of these, the toroidal continuously variable transmission 21 includes a pair of input side disks 2a and 2b, an output side disk 5a, a plurality of power rollers 6 and 6, and a plurality of trunnions 7 and 7 (see FIG. 4). ), A pressing device 9b, and a preload spring 10a (see FIGS. 4 to 5). Of these, the input-side disks 2a and 2b are arranged in close proximity to the both ends of the input-side rotating shaft 1b provided coaxially with the drive shaft 8a, with the inner side surfaces, each of which is a toroidal curved surface, facing each other. It is movable and supported so as to be able to rotate in synchronization with the input-side rotating shaft 1b. The output-side disk 5a has both side surfaces, each of which is a toroidal curved surface, positioned between the two input-side disks 2a, 2b with respect to the axial direction of the input-side rotating shaft 1b. In a state of being opposed to the inner side surface, it is supported coaxially with both the input side disks 2a and 2b and capable of relative rotation with respect to the both input side disks 2a and 2b. Note that the output side disk may be formed by combining a pair of elements as shown in FIG.

前記各パワーローラ６、６は、前記両入力側ディスク２ａ、２ｂの内側面と前記出力側ディスク５ａの両側面との間に挟持されて、これら両入力側ディスク２ａ、２ｂと出力側ディスク５ａとの間で動力（トルク）を伝達する。前記各トラニオン７、７は、前記各パワーローラ６、６を回転自在に支持しており、前記両入力側ディスク２ａ、２ｂ及び前記出力側ディスク５ａの中心軸に対し捩れの位置にある枢軸を中心とする揺動変位を可能に支持されている。前記押圧装置９ｂは、前記駆動軸８ａと、前記両入力側ディスク２ａ、２ｂのうちの一方（図１の右方）の入力側ディスク２ａとの間に設けられ、この一方の入力側ディスク２ａを、これら両入力側ディスク２ａ、２ｂのうちの他方（図１の左方）の入力側ディスク２ｂに向け押圧するものである。この様な押圧装置９ｂとしては、例えば、図４に示す様なローディングカム式、又は、図５に示す様な油圧式のものを使用する事ができる。前記予圧ばね１０ａは、前記入力側回転軸１ｂと前記一方の入力側ディスク２ａとの間に設けられ、この一方の入力側ディスク２ａを前記他方の入力側ディスク２ｂに向け押圧する方向の弾力を有する。これにより、前記押圧装置９ｂの非作動時にも、前記各パワーローラ６、６の周面と、前記両入力側ディスク２ａ、２ｂの内側面及び前記出力側ディスク５ｂの両側面との転がり接触部の面圧を、必要最低限だけは確保する様にしている。この結果、これら各転がり接触部は、前記トロイダル型無段変速機２１の運転開始直後から、過大な滑りを生じる事なく、動力伝達を開始する事ができる。この様な予圧ばね１０ａとしては、例えば、図４〜５に示す様な皿ばねを使用する事ができる。又、この予圧ばね１０ａの弾力は、図４に示す様なローディングナット１１の締め付け量を調節したり、図５に示す様な係止環１５の厚さ寸法を適宜選択する事により調整する。 The power rollers 6 and 6 are sandwiched between the inner side surfaces of the input side disks 2a and 2b and both side surfaces of the output side disk 5a, and both the input side disks 2a and 2b and the output side disk 5a. Power (torque) is transmitted between them. The trunnions 7 and 7 rotatably support the power rollers 6 and 6 and have pivots that are twisted with respect to the central axes of the input disks 2a and 2b and the output disk 5a. It is supported so as to be able to swing around the center. The pressing device 9b is provided between the drive shaft 8a and one input side disk 2a (right side in FIG. 1) of the two input side disks 2a and 2b, and this one input side disk 2a. Is pressed toward the other input side disk 2b (left side in FIG. 1) of the two input side disks 2a and 2b. As such a pressing device 9b, for example, a loading cam type as shown in FIG. 4 or a hydraulic type as shown in FIG. 5 can be used. The preload spring 10a is provided between the input side rotating shaft 1b and the one input side disk 2a, and has elasticity in a direction to press the one input side disk 2a toward the other input side disk 2b. Have. Thereby, even when the pressing device 9b is not operated, the rolling contact portion between the peripheral surface of each of the power rollers 6, 6 and the inner side surfaces of the both input side disks 2a, 2b and both side surfaces of the output side disk 5b. The minimum surface pressure is ensured. As a result, these rolling contact portions can start power transmission without causing excessive slip immediately after the start of operation of the toroidal continuously variable transmission 21. As such a preload spring 10a, for example, a disc spring as shown in FIGS. 4 to 5 can be used. The elasticity of the preload spring 10a is adjusted by adjusting the tightening amount of the loading nut 11 as shown in FIG. 4 or by appropriately selecting the thickness dimension of the locking ring 15 as shown in FIG.

前記無段変速装置の運転時には、前記駆動軸８ａにより、前記トロイダル型無段変速機２１を構成する一方の入力側ディスク２ａを、前記押圧装置９ｂを介して回転駆動する。この結果、前記入力回転軸１ｂの両端寄り部分に支持された１対の入力側ディスク２ａ、２ｂが、互いに近づく方向に押圧されつつ同期して回転する。そして、この回転が、前記各パワーローラ６、６を介して前記出力側ディスク５ａに伝わり、この出力側ディスク５ａの外周面に設けられた出力歯車４ａから取り出される。前記入力回転軸１ｂとこの出力歯車４ａとの間の変速比（トロイダル型無段変速機２１の変速比）を変える場合は、図示しないアクチュエータにより前記各トラニオン７、７をそれぞれの枢軸の軸方向に変位させる。この結果、前記各パワーローラ６、６の周面と、前記両入力側ディスク２ａ、２ｂの内側面及び前記出力側ディスク５ａの両側面との転がり接触部（トラクション部）に作用する、接線方向の力の向きが変化する（転がり接触部にサイドスリップが発生する）。そして、この力の向きの変化に伴って前記各トラニオン７、７が、それぞれの枢軸２５、２５を中心に揺動し、前記各パワーローラ６、６の周面と、前記両入力側ディスク２ａ、２ｂの内側面及び前記出力側ディスク５ａの両側面との接触位置が変化する。前記各パワーローラ６、６の周面を、前記両入力側ディスク２ａ、２ｂの内側面の径方向外寄り部分と、前記出力側ディスク５ａの両側面の径方向内寄り部分とに転がり接触させれば、前記入力回転軸１ｂと前記出力歯車４ａとの間の変速比が増速側になる。これに対して、前記各パワーローラ６、６の周面を、前記両入力側ディスク２ａ、２ｂの内側面の径方向内寄り部分と、前記出力側ディスク５ａの両側面の径方向外寄り部分とに転がり接触させれば、前記入力回転軸１ｂと前記出力歯車４ａとの間の変速比が減速側になる。 During operation of the continuously variable transmission, one input side disk 2a constituting the toroidal continuously variable transmission 21 is rotationally driven by the drive shaft 8a via the pressing device 9b. As a result, the pair of input-side disks 2a and 2b supported on the portions near both ends of the input rotation shaft 1b rotate synchronously while being pressed toward each other. Then, this rotation is transmitted to the output side disk 5a via the power rollers 6 and 6, and is taken out from the output gear 4a provided on the outer peripheral surface of the output side disk 5a. When changing the gear ratio between the input rotary shaft 1b and the output gear 4a (the gear ratio of the toroidal-type continuously variable transmission 21), the trunnions 7 and 7 are moved in the axial direction of the respective pivots by an actuator (not shown). Displace to. As a result, the tangential direction acting on the rolling contact portion (traction portion) between the peripheral surface of each of the power rollers 6, 6 and the inner side surfaces of both the input side discs 2a, 2b and both side surfaces of the output side disc 5a. The direction of the force changes (side slip occurs at the rolling contact portion). The trunnions 7 and 7 swing around the pivots 25 and 25 in accordance with the change in the direction of the force, and the peripheral surfaces of the power rollers 6 and 6 and the both input side disks 2a. The position of contact between the inner side surface of 2b and both side surfaces of the output side disk 5a changes. The peripheral surface of each of the power rollers 6 and 6 is brought into rolling contact with the radially outward portion of the inner side surfaces of the input side discs 2a and 2b and the radially inward portion of both side surfaces of the output side disc 5a. Then, the gear ratio between the input rotary shaft 1b and the output gear 4a is on the speed increasing side. On the other hand, the circumferential surfaces of the power rollers 6 and 6 are arranged such that the radially inner portions of the inner side surfaces of the input side disks 2a and 2b and the radially outer side portions of both side surfaces of the output side disk 5a. , The gear ratio between the input rotary shaft 1b and the output gear 4a becomes the deceleration side.

前記遊星歯車式変速機２２は、前記駆動軸８ａ及び前記トロイダル型無段変速機２１の出力歯車４ａと、前記出力軸２０との間に設けられている。この様な遊星歯車式変速機２２は、遊星歯車機構２６と、この出力軸２０の内側に回転自在に挿通された中間軸２７と、この中間軸２７の片端部（図１の左端部）に、この中間軸２７と同期した回転を可能に支持された中間歯車２８とを備えている。このうちの遊星歯車機構２６は、キャリア２９に回転可能に支持された遊星歯車３０、３０を、太陽歯車３１に噛合させると共に、リング歯車３２にも噛合させる、シングルピニオン式である。この太陽歯車３１は、前記中間軸２７の他端部（図１の右端部）に、この中間軸２７と同期した回転を可能に支持されている。前記キャリア２９は、複数の歯車を組み合わせて成る入力側歯車伝達機構３３を介して、前記駆動軸８ａにより回転駆動される。前記リング歯車３２は、前記クラッチ装置２３を構成する低速用クラッチ７を介して、前記出力軸２０を回転駆動可能としている。前記中間歯車２８は、前記出力歯車４ａと噛合すると共に、前記クラッチ装置２３を構成する高速用クラッチ８を介して、前記出力軸２０を回転駆動可能としている。 The planetary gear type transmission 22 is provided between the output shaft 20 and the drive shaft 8 a and the output gear 4 a of the toroidal-type continuously variable transmission 21. Such a planetary gear type transmission 22 has a planetary gear mechanism 26, an intermediate shaft 27 that is rotatably inserted inside the output shaft 20, and one end portion (left end portion in FIG. 1) of the intermediate shaft 27. And an intermediate gear 28 supported so as to be able to rotate in synchronization with the intermediate shaft 27. Of these, the planetary gear mechanism 26 is a single pinion type in which planetary gears 30 and 30 rotatably supported by a carrier 29 are meshed with a sun gear 31 and also meshed with a ring gear 32. The sun gear 31 is supported on the other end portion (the right end portion in FIG. 1) of the intermediate shaft 27 so as to be able to rotate in synchronization with the intermediate shaft 27. The carrier 29 is rotationally driven by the drive shaft 8a via an input side gear transmission mechanism 33 formed by combining a plurality of gears. The ring gear 32 can rotate the output shaft 20 via a low speed clutch 7 constituting the clutch device 23. The intermediate gear 28 meshes with the output gear 4 a and can rotate the output shaft 20 via the high-speed clutch 8 constituting the clutch device 23.

この出力軸２０の動力は、複数の歯車を組み合わせて成る出力側歯車伝達機構３４を介して、前記デファレンシャルギヤ１９の入力部に伝達可能としている。本例の場合、この出力側歯車伝達機構３４内に、湿式クラッチである前記出力側クラッチ機構２４を組み込んで、前記出力軸２０と前記デファレンシャルギヤ１９の入力部との間の動力伝達の断接状態を切り換え可能としている。この為に、前記出力側歯車伝達機構３４は、第一〜第三歯車３５〜３７と、互いに同軸に、且つ、相対回転を可能に支持された１対の回転軸３８ａ、３８ｂとを備える。前記第一歯車３５は、前記出力軸２０の中間部に、この出力軸２０と同期した回転を可能に支持されている。前記第二歯車３６は、前記第一歯車３５と噛合した状態で、前記両回転軸３８ａ、３８ｂのうちの一方（図１の右方）の回転軸３８ａの周囲に、この一方の回転軸３８ａと同期した回転を可能に支持されている。前記第三歯車３７は、前記デファレンシャルギヤ１９の入力部に動力伝達を可能とした状態で、前記両回転軸３８ａ、３８ｂのうちの他方（図１の左方）の回転軸３８ｂの周囲に、この他方の回転軸３８ｂと同期した回転を可能に支持されている。そして、前記出力側クラッチ機構２４を構成するクラッチディスク３９を前記一方の回転軸３８ａの端部に、この一方の回転軸３８ａと同期した回転を可能に支持固定すると共に、前記出力側クラッチ機構２４を構成するフライホイール４０を前記他方の回転軸３８ｂの端部に、この他方の回転軸３８ｂと同期した回転を可能に支持固定している。この様な出力側クラッチ機構２４は、前記無段変速装置を構成する他の部分（トロイダル型無段変速機２１、遊星歯車式変速機２２、クラッチ装置２３等）と共にハウジング内に収納する事もできるし、ハウジングの外に設ける事もできる。 The power of the output shaft 20 can be transmitted to the input portion of the differential gear 19 via an output side gear transmission mechanism 34 formed by combining a plurality of gears. In the case of this example, the output side gear transmission mechanism 34, which is a wet clutch, is incorporated in the output side gear transmission mechanism 34 to connect and disconnect the power transmission between the output shaft 20 and the input portion of the differential gear 19. The state can be switched. For this purpose, the output side gear transmission mechanism 34 includes first to third gears 35 to 37 and a pair of rotating shafts 38a and 38b supported coaxially with each other and capable of relative rotation. The first gear 35 is supported at an intermediate portion of the output shaft 20 so as to be able to rotate in synchronization with the output shaft 20. The second gear 36 is in mesh with the first gear 35 and around one rotary shaft 38a (right side in FIG. 1) of the rotary shafts 38a and 38b. It is supported to be able to rotate synchronously. The third gear 37 is in a state where power can be transmitted to the input portion of the differential gear 19 and around the other rotary shaft 38b of the rotary shafts 38a and 38b (left side in FIG. 1). The other rotating shaft 38b is supported so as to be able to rotate in synchronization. The clutch disk 39 constituting the output side clutch mechanism 24 is supported and fixed at the end of the one rotary shaft 38a so as to be able to rotate in synchronization with the one rotary shaft 38a, and the output side clutch mechanism 24. Is supported and fixed at the end of the other rotating shaft 38b so as to be able to rotate in synchronization with the other rotating shaft 38b. Such an output side clutch mechanism 24 may be housed in a housing together with other parts (toroidal continuously variable transmission 21, planetary gear transmission 22, clutch device 23, etc.) constituting the continuously variable transmission. Can be provided outside the housing.

上述の様な本例の無段変速装置は、前記クラッチ装置２３（を構成する低速クラッチ７及び高速クラッチ８）の断接状態を切り換える事により、前記駆動軸８ａを一方向に回転させた状態のまま前記出力軸２０の回転状態を、停止状態（所謂ギヤードニュートラル状態）を挟んで正転、逆転に切り換えられる低速モードと、この低速モードと比べて前記駆動軸８ａと前記出力軸２０との間の減速比が小さい高速モードとの何れかのモードで運転する。 In the continuously variable transmission of this example as described above, the drive shaft 8a is rotated in one direction by switching the connection / disconnection state of the clutch device 23 (the low-speed clutch 7 and the high-speed clutch 8 constituting the clutch device 23). The low-speed mode in which the rotation state of the output shaft 20 is switched between forward rotation and reverse rotation with a stop state (so-called geared neutral state) sandwiched between the drive shaft 8a and the output shaft 20 as compared with this low-speed mode. The vehicle is operated in one of the high speed mode with a small reduction ratio.

図２は、前記トロイダル型無段変速機２１の変速比と無段変速装置全体としての速度比との関係の１例を示している。例えば、前記低速用クラッチ７が接続され、前記高速用クラッチ８の接続が断たれた低速モードでは、実線αで示す様に、トロイダル型無段変速機２１の変速比を、ギヤードニュートラル状態を実現できる値（ＧＮ値、ギヤードニュートラルポイント）から減速側に変化させる程、無段変速装置全体としての速度比を停止状態（変速比０の状態）から前進方向（＋：正転方向）に、増速する方向に変化させられる。又、同じくＧＮ値から増速側に変化させる程、同じく停止状態から後退方向（−：逆転方向）に増速する方向に変化させられる。一方、前記高速用クラッチ８が接続され、前記低速用クラッチ７の接続が断たれた高速モードでは、実線βで示す様に、前記トロイダル型無段変速機２１の変速比を増速側に変化させる程、前記無段変速装置全体としての速度比を（前進方向に）増速側に変化させられる。即ち、本例の場合には、前記低速モードと前記高速モードとの切換を、前記トロイダル型無段変速機２１の変速比の最小変速比（最も減速側の変速比）で行う様にしている。 FIG. 2 shows an example of the relationship between the speed ratio of the toroidal type continuously variable transmission 21 and the speed ratio of the continuously variable transmission as a whole. For example, in the low speed mode in which the low speed clutch 7 is connected and the high speed clutch 8 is disconnected, the gear ratio of the toroidal-type continuously variable transmission 21 is realized in a geared neutral state as indicated by the solid line α. The speed ratio of the continuously variable transmission as a whole increases from the stop state (speed ratio 0 state) to the forward direction (+: forward rotation direction) as the value is changed from the possible value (GN value, geared neutral point) to the deceleration side. It can be changed in the direction of speed. Similarly, as the GN value is changed from the GN value to the speed increasing side, the speed is also changed from the stop state to the speed increasing direction in the reverse direction (-: reverse direction). On the other hand, in the high speed mode in which the high speed clutch 8 is connected and the low speed clutch 7 is disconnected, the speed ratio of the toroidal continuously variable transmission 21 is changed to the higher speed side as indicated by the solid line β. As a result, the speed ratio of the continuously variable transmission as a whole can be changed to the speed increasing side (in the forward direction). That is, in the case of this example, switching between the low speed mode and the high speed mode is performed at the minimum speed ratio (the speed ratio on the most deceleration side) of the toroidal-type continuously variable transmission 21. .

尚、一般的には、「変速比」は減速比であり、「速度比」は増速比であり、「変速比」の逆数が「速度比」となる（「速度比」＝１／「変速比」）。但し、本明細書では、トロイダル型無段変速機に関する入力側と出力側との間の比について「変速比」の言葉を用い、無段変速装置全体に関する入力側と出力側との間の比について「速度比」の言葉を用いている。この理由は、トロイダル型無段変速機の比なのか、無段変速装置全体としての比なのかを明確にし易くする為である。従って、本明細書では、「変速比」が減速比に、「速度比」が増速比に、必ずしも対応するものではない。 In general, “speed ratio” is a reduction ratio, “speed ratio” is an increase ratio, and the reciprocal of “speed ratio” is “speed ratio” (“speed ratio” = 1 / “ Gear ratio "). However, in this specification, the term “speed ratio” is used for the ratio between the input side and the output side for the toroidal-type continuously variable transmission, and the ratio between the input side and the output side for the entire continuously variable transmission. The term “speed ratio” is used. The reason for this is to make it easy to clarify whether it is the ratio of the toroidal type continuously variable transmission or the ratio of the continuously variable transmission as a whole. Therefore, in the present specification, the “speed ratio” does not necessarily correspond to the reduction ratio, and the “speed ratio” does not necessarily correspond to the speed increase ratio.

特に本例の無段変速装置の場合は、前記トロイダル型無段変速機２１の変速比を、前記低速モードと前記高速モードとを切り換える際の変速比（ＭＣ値、モード切換ポイント）に一致させる（トロイダル型無段変速機２１の変速比を最小変速比にする）と共に、前記低速用クラッチ７と前記高速用クラッチ８とを同時に接続し、且つ、前記出力側クラッチ機構２４を切断した状態で、前記駆動源を始動する様にしている。そして、この駆動源の回転が十分に上昇し（駆動源の回転数が安定し）、前記押圧装置９ｂの油圧室に導入される油圧が十分に（トラクション部で過大な滑りを生じる事なく、動力伝達を開始できる面圧を確保できる程度に）上昇するまで待機する。前記押圧装置９ｂの油圧室に導入される油圧が十分に上昇したら、その時点での無段変速装置の運転状態に応じて、前記低速用クラッチ７と前記高速用クラッチ８とのうちの何れか一方のクラッチを接続したままの状態で、他方のクラッチを切断すると共に、前記トロイダル型無段変速機２１の変速比を前記運転状態に応じた最適な値に調節する。具体的には、前記低速用クラッチ７を接続したままの状態で、前記高速用クラッチ８を切断すると共に、前記トロイダル型無段変速機２１の変速比を、ギヤードニュートラル状態を実現できる値に調節する。そして、前記出力側クラッチ機構２４を接続して、前記駆動源の動力を、前記無段変速装置により変速して、前記デファレンシャルギヤ１９の入力部に伝達する。 Particularly, in the case of the continuously variable transmission of this example, the transmission ratio of the toroidal type continuously variable transmission 21 is made to coincide with the transmission ratio (MC value, mode switching point) when switching between the low speed mode and the high speed mode. (With the transmission gear ratio of the toroidal-type continuously variable transmission 21 set to the minimum transmission gear ratio), the low speed clutch 7 and the high speed clutch 8 are simultaneously connected, and the output side clutch mechanism 24 is disconnected. The drive source is started. Then, the rotation of the drive source is sufficiently increased (the rotation speed of the drive source is stabilized), and the hydraulic pressure introduced into the hydraulic chamber of the pressing device 9b is sufficiently (without causing excessive slip at the traction portion, Wait until it rises (to the extent that the surface pressure that can start power transmission is secured). When the hydraulic pressure introduced into the hydraulic chamber of the pressing device 9b is sufficiently increased, one of the low speed clutch 7 and the high speed clutch 8 is selected according to the operating state of the continuously variable transmission at that time. While one clutch is still connected, the other clutch is disconnected and the transmission ratio of the toroidal continuously variable transmission 21 is adjusted to an optimum value according to the operating state. Specifically, the high-speed clutch 8 is disconnected while the low-speed clutch 7 remains connected, and the gear ratio of the toroidal continuously variable transmission 21 is adjusted to a value that can realize a geared neutral state. To do. Then, the output side clutch mechanism 24 is connected, and the power of the drive source is shifted by the continuously variable transmission and transmitted to the input portion of the differential gear 19.

上述の様な無段変速装置の運転を停止する際には、先ず、前記出力側クラッチ機構２４を切断する。次に、前記トロイダル型無段変速機２１の変速比を前記モード切換ポイントに一致させる（トロイダル型無段変速機２１の変速比を最小変速比にする）。そして、前記低速用クラッチ７と前記高速用クラッチ８とを何れも接続した状態とする。 When stopping the operation of the continuously variable transmission as described above, first, the output side clutch mechanism 24 is disconnected. Next, the transmission ratio of the toroidal continuously variable transmission 21 is made to coincide with the mode switching point (the transmission ratio of the toroidal continuously variable transmission 21 is set to the minimum transmission ratio). The low speed clutch 7 and the high speed clutch 8 are both connected.

上述の様な本例の無段変速装置によれば、前記トロイダル型無段変速機２１の伝達効率を確保しつつ、極低温環境下においても、運転開始直後からこのトロイダル型無段変速機２１のトラクション部で過大な滑りを生じる事なく、動力伝達を開始する事ができる。
即ち、本例の場合、前記トロイダル型無段変速機２１の変速比をモード切換ポイントに一致させると共に、前記低速用クラッチ７と前記高速用クラッチ８とを同時に接続した状態で、前記駆動源を始動する様にしている。この為、この駆動源の始動時（トロイダル型無段変速機２１の運転開始直後）に、このトロイダル型無段変速機２１を通過するトルクを小さくする（理想的には、トロイダル型無段変速機２１を通過するトルクを０にして、１対の入力側ディスク２ａ、２ｂと出力側ディスク５ａとの間でトルクが伝達されない様にする）事ができる。この為、前記予圧ばね１０ａの弾力を小さく抑える事ができる。この結果、この予圧ばね１０ａの突き当て部の摩耗を少なく抑える事ができる。又、前記トロイダル型無段変速機２１の運転開始直後であるか否かにかかわらず、このトロイダル型無段変速機２１を通過するトルクが小さい場合に、前記各トラクション部の面圧が過大になる事を防止して、前記トロイダル型無段変速機２１の伝達効率を確保する事ができる。尚、このトロイダル型無段変速機２１の運転開始直後に、このトロイダル型無段変速機２１を通過するトルクをほぼ０にできる場合には、予圧ばね１０ａを省略する事もできる。 According to the continuously variable transmission of this example as described above, the toroidal continuously variable transmission 21 is started immediately after the start of operation even in an extremely low temperature environment while ensuring the transmission efficiency of the toroidal continuously variable transmission 21. Power transmission can be started without causing excessive slip at the traction section.
That is, in the case of this example, the gear ratio of the toroidal-type continuously variable transmission 21 is made to coincide with the mode switching point, and the drive source is turned on while the low speed clutch 7 and the high speed clutch 8 are simultaneously connected. I try to start. For this reason, when the drive source is started (immediately after the start of operation of the toroidal continuously variable transmission 21), the torque passing through the toroidal continuously variable transmission 21 is reduced (ideally, the toroidal continuously variable transmission). The torque passing through the machine 21 can be set to zero so that torque is not transmitted between the pair of input side disks 2a, 2b and the output side disk 5a. For this reason, the elasticity of the preload spring 10a can be kept small. As a result, it is possible to suppress wear of the abutting portion of the preload spring 10a. Regardless of whether the toroidal type continuously variable transmission 21 has just started operation or not, when the torque passing through the toroidal type continuously variable transmission 21 is small, the surface pressure of each of the traction sections becomes excessive. Therefore, the transmission efficiency of the toroidal continuously variable transmission 21 can be ensured. If the torque passing through the toroidal continuously variable transmission 21 can be made almost zero immediately after the operation of the toroidal continuously variable transmission 21 is started, the preload spring 10a can be omitted.

更に、本例の場合には、前記トロイダル型無段変速機２１の運転開始直後に、このトロイダル型無段変速２１を通過するトルクを小さくできる為、前記予圧ばね１０ａの弾力を小さく抑えても、前記各トラクション部に存在する（トラクション部を潤滑する）トラクションオイルのトラクション係数が小さくなる、極低温環境下（例えば−４０℃以下）においても、前記トロイダル型無段変速機２１の運転開始直後から前記各トラクション部で過大な滑りを生じる事なく、動力伝達を開始する事ができる。 Furthermore, in the case of this example, immediately after the operation of the toroidal continuously variable transmission 21 is started, the torque passing through the toroidal continuously variable transmission 21 can be reduced, so that the elasticity of the preload spring 10a can be kept small. Immediately after the operation of the toroidal-type continuously variable transmission 21 is started even in an extremely low temperature environment (for example, −40 ° C. or less), in which the traction coefficient of the traction oil existing in each of the traction parts (lubricates the traction parts) becomes small. Therefore, power transmission can be started without causing excessive slip in each traction section.

尚、本例の場合には、前記駆動源の始動時に、前記出力側クラッチ機構２４を切断している為、この駆動源の回転が安定し、前記押圧装置９ｂの油圧室に導入される油圧が十分に上昇するまで（前記トロイダル型無段変速機２１のトラクション部で過大な滑りを生じる事なく、動力伝達を開始できる面圧を確保できるまで）、前記駆動源の動力は前記デファレンシャルギヤ１９の入力部に伝達される事はない。 In the case of this example, since the output side clutch mechanism 24 is disconnected when the drive source is started, the rotation of the drive source is stabilized and the hydraulic pressure introduced into the hydraulic chamber of the pressing device 9b. Is sufficiently increased (until the surface pressure capable of starting power transmission is ensured without causing excessive slip at the traction portion of the toroidal-type continuously variable transmission 21), the power of the drive source is the differential gear 19. Is not transmitted to the input section.

尚、本発明の無段変速装置を実施する場合に、トロイダル型無段変速機２１は、１対の出力側ディスクを回転軸の両端寄り部分に、互いに同期した回転を可能に支持すると共に、この回転軸の軸方向に関して、前記両出力側ディスクの間位置に、一体型又は１対の素子を結合して成る入力側ディスクを、これら両出力側ディスクと同軸に、且つ、これら両出力側ディスクに対する相対回転を可能に支持する様に構成しても良い。又、トロイダル型無段変速機２１を、入力側ディスクと出力側ディスクとを１個ずつ設けた、所謂シングキャビティ型とする事もできる。又、前記トロイダル型無段変速機２１は、ハーフトロイダル型に限らず、フルトロイダル型としても良い。更に、本発明は、ギヤードニュートラル状態を実現できないトロイダル型無段変速機で実施する事もできる。 When implementing the continuously variable transmission of the present invention, the toroidal continuously variable transmission 21 supports a pair of output-side disks on both ends of the rotating shaft so as to be able to rotate in synchronization with each other, With respect to the axial direction of the rotating shaft, an input-side disk formed by connecting a single element or a pair of elements at a position between the two output-side disks is coaxial with these two output-side disks and both these output-side disks. You may comprise so that relative rotation with respect to a disk may be supported. The toroidal type continuously variable transmission 21 may be a so-called single cavity type in which one input side disk and one output side disk are provided. The toroidal continuously variable transmission 21 is not limited to the half toroidal type but may be a full toroidal type. Furthermore, the present invention can be implemented by a toroidal type continuously variable transmission that cannot realize the geared neutral state.

［実施の形態の第２例］
図３は、本発明の実施の形態の第２例を示している。本例の無段変速装置は、出力軸２０の動力をデファレンシャルギヤ１９の入力部に伝達する為の出力側歯車伝達機構３４ａ内に、ドグクラッチ４１を組み込む事により、前記出力軸２０と前記デファレンシャルギヤ１９の入力部との間の動力伝達の断接状態を切り換え可能としている。この様な本例によれば、駆動源を始動し、押圧装置９ｂの油圧室に導入される油圧が十分に上昇した後、速やかに、前記出力軸２０の動力を前記デファレンシャルギヤ１９の入力部に伝達する事ができる。
その他の部分の構成及び作用は、上述した実施の形態の第１例と同様である。 [Second Example of Embodiment]
FIG. 3 shows a second example of the embodiment of the present invention. The continuously variable transmission of the present example incorporates a dog clutch 41 into the output side gear transmission mechanism 34a for transmitting the power of the output shaft 20 to the input portion of the differential gear 19, whereby the output shaft 20 and the differential gear are assembled. The connection / disconnection state of power transmission with 19 input units can be switched. According to this example, after the drive source is started and the hydraulic pressure introduced into the hydraulic chamber of the pressing device 9b has sufficiently increased, the power of the output shaft 20 is quickly supplied to the input portion of the differential gear 19. Can be communicated to.
The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

本発明の無段変速装置は、車両用や建設機械用、ポンプ等の各種産業機械用の自動変速装置として利用するだけでなく、航空機等で使用される発電機用の自動変速装置として利用する事もできる。即ち、航空機の駆動源であるエンジンは、通常約４５００〜９２００［ｍｉｎ^−１］の速度で回転するのに対し、前記航空機に搭載される発電機（交流発電機）の回転子（ロータ）は、約２４０００［ｍｉｎ^−１］の速度で回転する必要がある。この様な発電機が発電する電力の周波数を安定させる為には、この発電機の回転子を一定の速度で回転させる必要がある。そこで、前記航空機のエンジンと発電機との間に、本発明の無段変速装置を組み込めば、前記発電機の回転子を一定の速度で回転させて、電力の周波数を安定させる事ができる。尚、航空機は、寒冷地でエンジンを始動しなければならない場合があり、エンジンと発電機との間に、本発明の無段変速装置を組み込む事が有効である。 The continuously variable transmission of the present invention is used not only as an automatic transmission for various industrial machines such as vehicles, construction machines, and pumps, but also as an automatic transmission for generators used in aircrafts and the like. You can also do things. That is, an engine that is a driving source of an aircraft normally rotates at a speed of about 4500 to 9200 [min ⁻¹ ], whereas a rotor (rotor) of a generator (alternator) mounted on the aircraft is It is necessary to rotate at a speed of about 24000 [min ⁻¹ ]. In order to stabilize the frequency of the power generated by such a generator, it is necessary to rotate the rotor of this generator at a constant speed. Therefore, if the continuously variable transmission of the present invention is incorporated between the aircraft engine and the generator, the rotor of the generator can be rotated at a constant speed to stabilize the frequency of the electric power. An aircraft may have to start an engine in a cold region, and it is effective to incorporate the continuously variable transmission of the present invention between the engine and the generator.

１、１ａ入力回転軸
２ａ、２ｂ入力側ディスク
３出力筒
４出力歯車
５、５ａ出力側ディスク
６パワーローラ
７トラニオン
８駆動軸
９、９ａ、９ｂ押圧装置
１０ａ、１０ｂ予圧ばね
１１ローディングナット
１２スプライン孔
１３スプライン軸部
１４係止溝
１５係止環
１６抑え環
１７止め輪
１８ボールスプライン
１９デファレンシャルギヤ
２０出力軸
２１トロイダル型無段変速機
２２遊星歯車式変速機
２３クラッチ機構
２４出力側クラッチ機構
２５枢軸
２６遊星歯車機構
２７中間軸
２８中間歯車
２９キャリア
３０遊星歯車
３１太陽歯車
３２リング歯車
３３入力側歯車伝達機構
３４出力側歯車伝達機構
３５第一歯車
３６第二歯車
３７第三歯車
３８ａ、３８ｂ回転軸
３９クラッチディスク
４０フライホイール
４１ドグクラッチ DESCRIPTION OF SYMBOLS 1, 1a Input rotary shaft 2a, 2b Input side disk 3 Output cylinder 4 Output gear 5, 5a Output side disk 6 Power roller 7 Trunnion 8 Drive shaft 9, 9a, 9b Pressing device 10a, 10b Preload spring 11 Loading nut 12 Spline hole DESCRIPTION OF SYMBOLS 13 Spline shaft part 14 Locking groove 15 Locking ring 16 Retaining ring 17 Retaining ring 18 Ball spline 19 Differential gear 20 Output shaft 21 Toroidal type continuously variable transmission 22 Planetary gear type transmission 23 Clutch mechanism 24 Output side clutch mechanism 25 Axis 26 planetary gear mechanism 27 intermediate shaft 28 intermediate gear 29 carrier 30 planetary gear 31 sun gear 32 ring gear 33 input side gear transmission mechanism 34 output side gear transmission mechanism 35 first gear 36 second gear 37 third gear 38a, 38b rotating shaft 39 Clutch disc 40 Flywheel 41 dog clutch

Claims

An input member that is rotationally driven in one direction by a drive source, an output member for rotationally driving the driven part, a toroidal-type continuously variable transmission, and a gear-type differential mechanism formed by combining a plurality of gears; The toroidal continuously variable transmission and a clutch device for switching the power transmission state between the differential mechanism,
Of these, the clutch device is connected when realizing a low-speed mode with a large reduction ratio between the input member and the output member, and is disconnected when realizing a high-speed mode with a small reduction ratio. A clutch for high speed and a high speed clutch which is connected when realizing the high speed mode and is disconnected when realizing the low speed mode.
In the continuously variable transmission,
In the state where the gear ratio of the toroidal type continuously variable transmission matches the gear ratio at the time of switching between the low speed mode and the high speed mode, and the low speed and high speed clutches are simultaneously connected, Start,
A continuously variable transmission characterized by that.