JP4561126B2

JP4561126B2 - Toroidal continuously variable transmission

Info

Publication number: JP4561126B2
Application number: JP2004060131A
Authority: JP
Inventors: 功久小林
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2004-03-04
Filing date: 2004-03-04
Publication date: 2010-10-13
Anticipated expiration: 2024-03-04
Also published as: JP2005249070A

Description

この発明に係るトロイダル型無段変速機は、例えば自動車用自動変速装置を構成する変速ユニットとして、或はポンプ等の各種産業機械の運転速度を調節する為の変速装置として利用する。 The toroidal continuously variable transmission according to the present invention is used, for example, as a transmission unit constituting an automatic transmission for automobiles or as a transmission for adjusting the operating speed of various industrial machines such as pumps.

例えば特許文献１〜２等に記載されている様に、自動車用自動変速装置の変速ユニットとして、図４〜６に示す様なトロイダル型無段変速機を使用する事が研究され、一部で実施されている。このトロイダル型無段変速機は、ダブルキャビティ型と呼ばれるもので、特許請求の範囲に記載した回転軸である入力回転軸１の周囲に、それぞれが特許請求の範囲に記載した外側ディスクである１対の入力側ディスク２ａ、２ｂを支持している。これら両入力側ディスク２ａ、２ｂは上記入力回転軸１に対し、それぞれがトロイド曲面（断面円弧形の凹面）であって特許請求の範囲に記載した軸方向片側面に相当する入力側内側面３、３同士を互いに対向させた状態で、それぞれボールスプライン４、４を介して支持している。従って上記両入力側ディスク２ａ、２ｂは、互いに同心に、且つ、同期した回転を自在に支持されている。 For example, as described in Patent Documents 1 and 2, etc., it has been studied to use a toroidal continuously variable transmission as shown in FIGS. 4 to 6 as a transmission unit of an automatic transmission for an automobile. It has been implemented. This toroidal-type continuously variable transmission is called a double cavity type, and each is an outer disk 1 around the input rotary shaft 1 which is the rotary shaft described in the claims. The pair of input side disks 2a and 2b is supported. These input side disks 2a and 2b are each a toroidal curved surface (concave arc-shaped concave surface) with respect to the input rotation shaft 1, and the input side inner surface corresponding to one axial side surface recited in the claims. 3 and 3 are supported via ball splines 4 and 4 in a state of being opposed to each other. Therefore, both the input side disks 2a and 2b are supported concentrically and freely in a synchronized manner.

又、上記入力回転軸１の中間部は、トロイダル型無段変速機を収納したケーシング５内に設置した隔壁部６に設けた通孔７を挿通している。この通孔７の内径側には、円筒状の出力筒８を、１対の転がり軸受９、９により回転自在に支持しており、この出力筒８の中間部外周面に出力歯車１０を固設している。又、この出力筒８の両端部で上記隔壁部６の両外側面から突出した部分に、それぞれが特許請求の範囲に記載した内側ディスクに相当する出力側ディスク１１ａ、１１ｂを、スプライン係合により、上記出力筒８と同期した回転自在に支持している。この状態で、それぞれがトロイド曲面であって特許請求の範囲に記載した軸方向側面に相当する、上記両出力側ディスク１１ａ、１１ｂの出力側内側面１２、１２が、上記両入力側内側面３、３に対向する。 Further, the intermediate portion of the input rotary shaft 1 is inserted through a through hole 7 provided in a partition wall portion 6 installed in a casing 5 housing a toroidal type continuously variable transmission. A cylindrical output cylinder 8 is rotatably supported by a pair of rolling bearings 9 and 9 on the inner diameter side of the through hole 7, and an output gear 10 is fixed to the outer peripheral surface of the intermediate portion of the output cylinder 8. Has been established. In addition, the output side disks 11a and 11b corresponding to the inner disks described in the claims are respectively connected to the portions protruding from both outer side surfaces of the partition wall 6 at both ends of the output cylinder 8 by spline engagement. The output cylinder 8 is rotatably supported in synchronization with the output cylinder 8. In this state, the output side inner surfaces 12 and 12 of the output side disks 11a and 11b, each of which is a toroidal curved surface and corresponding to the axial side surface recited in the claims, are the input side inner side surfaces 3 of the input side. 3 is opposed.

又、上記入力回転軸１の周囲で上記入力側、出力側両内側面３、１２同士の間部分（キャビティ）に、それぞれ複数個（一般的には２個又は３個）ずつのパワーローラ１３ａ、１３ｂを配置している。これら各パワーローラ１３ａ、１３ｂはそれぞれ、上記入力側、出力側両内側面３、１２に転がり接触する周面１４、１４を球状凸面としたもので、特許請求の範囲の請求項１に記載した支持部材であるトラニオン１５ａ、１５ｂの内側面に、偏心軸１６、１６と、ラジアルニードル軸受１７、１７と、スラスト玉軸受１８、１８と、スラストニードル軸受１９、１９とにより、回転及び若干の揺動変位自在に支持されている。 Further, a plurality of (generally two or three) power rollers 13a are provided in a portion (cavity) between the input side and output side inner side surfaces 3 and 12 around the input rotary shaft 1. 13b. Each of these power rollers 13a and 13b has a spherical convex surface on the peripheral surfaces 14 and 14 that are in rolling contact with the input and output side inner surfaces 3 and 12, respectively, and is described in claim 1 of the claims. The inner surfaces of the trunnions 15a and 15b, which are supporting members, are rotated and slightly shaken by the eccentric shafts 16 and 16, radial needle bearings 17 and 17, thrust ball bearings 18 and 18, and thrust needle bearings 19 and 19, respectively. It is supported so that it can be moved and displaced.

即ち、上記各偏心軸１６、１６は基半部と先半部とが互いに偏心しており、このうちの基半部を上記各トラニオン１５ａ、１５ｂの中間部に、別のラジアルニードル軸受２０、２０により、揺動変位自在に支持している。上記各パワーローラ１３ａ、１３ｂは、この様な偏心軸１６、１６の先半部に、上記ラジアルニードル軸受１７、１７と上記スラスト玉軸受１８、１８とにより、回転自在に支持している。又、構成各部材の弾性変形に基づく、上記入力回転軸１の軸方向に関する上記各パワーローラ１３ａ、１３ｂの変位を、上記別のラジアルニードル軸受２０、２０と上記各スラストニードル軸受１９、１９とにより、自在としている。 That is, each of the eccentric shafts 16 and 16 has a base half portion and a tip half portion which are eccentric to each other, and the base half portion of the eccentric shafts 16 and 16 is arranged in the middle portion of the trunnions 15a and 15b. Thus, it is supported so as to be freely oscillating and displaceable. The power rollers 13a and 13b are rotatably supported by the radial needle bearings 17 and 17 and the thrust ball bearings 18 and 18 on the tip half portions of the eccentric shafts 16 and 16, respectively. Further, the displacement of each of the power rollers 13a and 13b with respect to the axial direction of the input rotary shaft 1 based on the elastic deformation of each constituent member is changed to the other radial needle bearings 20 and 20 and the thrust needle bearings 19 and 19, respectively. Because of this, it is free.

又、上記各トラニオン１５ａ、１５ｂは、それぞれの長さ方向（図５の表裏方向、図４、６の上下方向）両端部にこれら各トラニオン１５ａ、１５ｂ毎に互いに同心に設けられた枢軸２１、２１を中心として揺動変位自在である。これら各トラニオン１５ａ、１５ｂを揺動（傾斜）させる動作は、油圧式のアクチュエータ２２、２２によりこれら各トラニオン１５ａ、１５ｂを上記各枢軸２１、２１の軸方向に変位させる事により行なう。上記各アクチュエータ２２、２２の受圧面積は、互いに等しく（同径のものを使用）している。変速時には、上記各アクチュエータ２２、２２への圧油の給排により、上記各トラニオン１５ａ、１５ｂを上記各枢軸２１、２１の軸方向に変位させる。この結果、上記各パワーローラ１３ａ、１３ｂの周面１４、１４と上記入力側、出力側各ディスク２ａ、２ｂ、１１ａ、１１ｂの入力側、出力側各内側面３、１２との接触部（トラクション部）の接線方向に作用する力の方向が変化するので、上記各トラニオン１５ａ、１５ｂが上記各枢軸２１、２１を中心として揺動変位する。 Each trunnion 15a, 15b has a pivot 21 provided concentrically with each other for each trunnion 15a, 15b at both ends in the length direction (front and back direction in FIG. 5, vertical direction in FIGS. 4, 6). 21 can be oscillated and displaced freely. The operation of swinging (tilting) the trunnions 15a and 15b is performed by displacing the trunnions 15a and 15b in the axial directions of the pivots 21 and 21 by hydraulic actuators 22 and 22, respectively. The pressure receiving areas of the actuators 22 are equal to each other (use the same diameter). At the time of shifting, the trunnions 15a and 15b are displaced in the axial direction of the pivots 21 and 21 by supplying and discharging pressure oil to and from the actuators 22 and 22, respectively. As a result, contact portions (traction) between the peripheral surfaces 14 and 14 of the power rollers 13a and 13b and the input and output inner surfaces 3 and 12 of the input and output disks 2a, 2b, 11a and 11b. Since the direction of the force acting in the tangential direction of the part) changes, the trunnions 15a and 15b swing and displace around the pivots 21 and 21, respectively.

上述の様なトロイダル型無段変速機の運転時には、エンジン等の動力源に繋がる駆動軸２３により一方（図４〜５の左方）の入力側ディスク２ａを、ローディングカム式の押圧装置２４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、上記各パワーローラ１３ａ、１３ｂを介して上記両出力側ディスク１１ａ、１１ｂに伝わり、前記出力歯車１０から取り出される。 During operation of the toroidal-type continuously variable transmission as described above, the drive shaft 23 connected to the power source of the engine or the like is used to connect one input side disk 2a (the left side in FIGS. 4 to 5) to the loading cam type pressing device 24. To rotate through. 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 11a and 11b via the power rollers 13a and 13b, and is taken out from the output gear 10.

上記入力回転軸１と出力歯車１０との回転速度の比を変える場合で、先ず入力回転軸１と出力歯車１０との間で減速を行なう場合には、上記各トラニオン１５ａ、１５ｂを図５に示す位置に揺動させ、上記各パワーローラ１３ａ、１３ｂの周面１４、１４をこの図５に示す様に、上記両入力側ディスク２ａ、２ｂの入力側内側面３、３の中心寄り部分と上記両出力側ディスク１１ａ、１１ｂの出力側内側面１２、１２の外周寄り部分とにそれぞれ転がり接触させる。反対に、増速を行なう場合には、上記各トラニオン１５ａ、１５ｂを図５と反対方向に揺動させ、上記各パワーローラ１３ａ、１３ｂの周面１４、１４を、図５に示した状態とは逆に、上記両入力側ディスク２ａ、２ｂの入力側内側面３、３の外周寄り部分と上記両出力側ディスク１１ａ、１１ｂの出力側内側面１２、１２の中心寄り部分とにそれぞれ転がり接触させる。上記各トラニオン１５ａ、１５ｂの揺動角度を中間にすれば、上記入力回転軸１と出力歯車１０との間で、中間の速度比（変速比）を得られる。 When the ratio of the rotational speeds of the input rotary shaft 1 and the output gear 10 is changed and when deceleration is first performed between the input rotary shaft 1 and the output gear 10, the trunnions 15a and 15b are shown in FIG. As shown in FIG. 5, the peripheral surfaces 14, 14 of the power rollers 13a, 13b are pivoted to the positions shown in FIG. Each of the output side disks 11a and 11b is brought into rolling contact with the outer peripheral portions of the output side inner surfaces 12 and 12, respectively. On the contrary, when the speed is increased, the trunnions 15a and 15b are swung in the direction opposite to that shown in FIG. 5, and the peripheral surfaces 14 and 14 of the power rollers 13a and 13b are changed to the state shown in FIG. On the contrary, it is in rolling contact with the outer peripheral portion of the input side inner surfaces 3, 3 of the input side disks 2a, 2b and the central portion of the output side inner surfaces 12, 12 of the output side disks 11a, 11b. Let If the swing angles of the trunnions 15a and 15b are set to the middle, an intermediate speed ratio (transmission ratio) can be obtained between the input rotary shaft 1 and the output gear 10.

尚、上述の様なダブルキャビティ型のトロイダル型無段変速機では、各キャビティ同士の間で、伝達するトルクの大きさを同じにしている。この為に、前記各アクチュエータ２２、２２内に存在する高圧室と低圧室との油圧の差を、これら各アクチュエータ２２、２２同士の間で、互いに等しくしている。トロイダル型無段変速機の技術分野で周知の様に、上記各アクチュエータ２２、２２は、所謂２Ｆｔと呼ばれる、上記両キャビティ部分で伝達するトルクに比例したスラスト力が加わる。従って、上記各アクチュエータ２２、２２内に存在する高圧室と低圧室との油圧の差を、これら各アクチュエータ２２、２２同士の間で互いに等しくすれば、上記各パワーローラ１３ａ、１３ｂが伝達するトルクが互いに等しくなる。この様に、これら各パワーローラ１３ａ、１３ｂが伝達するトルクを互いに等しくする事で、一部のパワーローラに過度な負担が加わる事を防止し、伝達効率及び耐久性の確保を図っている。又、ダブルキャビティ型のトロイダル型無段変速機と遊星歯車式の変速機とを組み合わせた無段変速装置に関する発明が、例えば特許文献３に記載されて従来から知られている。又、押圧装置として油圧式のものを使用する事も、上記特許文献３に記載される等により、従来から知られている。 In the double cavity type toroidal continuously variable transmission as described above, the magnitude of the torque transmitted between the cavities is the same. For this reason, the hydraulic pressure difference between the high pressure chamber and the low pressure chamber existing in the actuators 22 and 22 is made equal between the actuators 22 and 22. As is well known in the technical field of toroidal-type continuously variable transmissions, the actuators 22 and 22 are subjected to a so-called 2Ft thrust force proportional to the torque transmitted through the two cavity portions. Therefore, if the difference in hydraulic pressure between the high pressure chamber and the low pressure chamber existing in each actuator 22, 22 is made equal between each actuator 22, 22, the torque transmitted by each power roller 13 a, 13 b Are equal to each other. In this way, by making the torque transmitted by each of these power rollers 13a and 13b equal to each other, it is possible to prevent an excessive load from being applied to some of the power rollers and to ensure transmission efficiency and durability. Also, an invention relating to a continuously variable transmission in which a double cavity type toroidal continuously variable transmission and a planetary gear type transmission are combined is described in, for example, Patent Document 3 and is conventionally known. Also, the use of a hydraulic device as a pressing device has been conventionally known as described in Patent Document 3 above.

上述の様なトロイダル型無段変速機の運転時には、押圧装置２４に近い側（図４〜５の左側）のキャビティと、同じく遠い側（図４〜５の右側）のキャビティとで、各キャビティを構成する入力側ディスク２ａ、２ｂを出力側ディスク１１ａ、１１ｂに押圧する力が異なる事が避けられない。具体的には、上記押圧装置２４に近い側のキャビティを構成する入力側ディスク２ａに加わる押圧力に比べて、上記遠い側のキャビティを構成する入力側ディスク２ｂに加わる押圧力が小さくなる。この理由は、次の通りである。 When the toroidal-type continuously variable transmission as described above is operated, each cavity includes a cavity on the side close to the pressing device 24 (left side in FIGS. 4 to 5) and a cavity on the far side (right side in FIGS. 4 to 5). It is inevitable that the forces for pressing the input-side discs 2a and 2b constituting the output side discs 11a and 11b are different. Specifically, the pressing force applied to the input side disk 2b constituting the far side cavity is smaller than the pressing force applied to the input side disk 2a constituting the cavity close to the pressing device 24. The reason for this is as follows.

上記押圧装置２４に近い側のキャビティを構成する入力側ディスク２ａには、この押圧装置２４が発生する押圧力が直接加わる。従って、これら押圧装置２４と入力側ディスク２ａとの間で、この押圧力が低下する程度は、この入力側ディスク２ａの内径側に設けたボールスプライン４の転がり抵抗に基づくだけの、極く僅かである。これに対して、上記押圧装置２４が発生した押圧力が上記遠い側のキャビティを構成する入力側ディスク２ｂに伝わる迄の間には、多くの抵抗が存在する。 A pressing force generated by the pressing device 24 is directly applied to the input side disk 2a constituting the cavity close to the pressing device 24. Therefore, the degree to which the pressing force decreases between the pressing device 24 and the input side disk 2a is very small, based on the rolling resistance of the ball spline 4 provided on the inner diameter side of the input side disk 2a. It is. On the other hand, many resistances exist until the pressing force generated by the pressing device 24 is transmitted to the input side disk 2b constituting the far side cavity.

具体的には、上記入力側ディスク２ａの内径側に設けたボールスプライン４の転がり抵抗に加え、次の(1) 〜(4) 部分が、上記遠い側のキャビティを構成する入力側ディスク２ｂに加わる押圧力を低下させる抵抗として働く。
(1) 前記駆動軸２３から上記押圧装置２４を構成するカム板２５に駆動力を伝達する為の凹凸係合部２６の、前記入力回転軸１の軸方向の変位に対する摩擦抵抗。
(2) 上記駆動軸２３の先端部外周面と前記入力回転軸１の基端部内周面との間に設けたブッシュ２７の、上記入力回転軸１の軸方向の変位に対する摩擦抵抗。
(3) 前記各出力側ディスク１１ａ、１１ｂの内周面と上記入力回転軸１の外周面との間に設けたラジアルニードル軸受２８、２８の、上記入力回転軸１の軸方向の変位に対する摩擦抵抗。
(4) 上記入力回転軸１の先端部をハウジング５に回転自在に支持する為のラジアルニードル軸受２９の、上記入力回転軸１の軸方向の変位に対する摩擦抵抗。
これら各部分の摩擦抵抗は、上記押圧力を伝達すべく、上記入力回転軸１が図４〜５の左方に変位する事に対する抵抗になって、その分、上記遠い側のキャビティを構成する入力側ディスク２ｂに加わる押圧力を低下させる。 Specifically, in addition to the rolling resistance of the ball spline 4 provided on the inner diameter side of the input side disk 2a, the following (1) to (4) portions are formed on the input side disk 2b constituting the far side cavity. Acts as a resistance to reduce the applied pressure.
(1) Friction resistance against the displacement in the axial direction of the input rotary shaft 1 of the concave and convex engaging portion 26 for transmitting a driving force from the driving shaft 23 to the cam plate 25 constituting the pressing device 24.
(2) Friction resistance against the axial displacement of the input rotary shaft 1 of the bush 27 provided between the outer peripheral surface of the distal end portion of the drive shaft 23 and the inner peripheral surface of the base end portion of the input rotary shaft 1.
(3) Friction with respect to the axial displacement of the input rotary shaft 1 of the radial needle bearings 28, 28 provided between the inner peripheral surfaces of the output side disks 11a, 11b and the outer peripheral surface of the input rotary shaft 1 resistance.
(4) Friction resistance against the axial displacement of the input rotary shaft 1 of the radial needle bearing 29 for rotatably supporting the tip end portion of the input rotary shaft 1 on the housing 5.
The frictional resistance of these parts becomes resistance against the displacement of the input rotary shaft 1 to the left in FIGS. 4 to 5 in order to transmit the pressing force, so that the far side cavity is formed accordingly. The pressing force applied to the input side disk 2b is reduced.

この様な原因で上記押圧装置２４から遠い側のキャビティを構成する入力側ディスク２ｂに加わる押圧力が、前記近い側のキャビティを構成する入力側ディスク２ａに加わる押圧力よりも低くなると、トロイダル型無段変速機の伝達効率確保と耐久性確保とを、高次元で両立させる事が難しくなる。この理由は、次の通りである。即ち、伝達効率を確保する為には、前記各入力側内側面３、３及び前記各出力側内側面１２、１２と、前記各パワーローラ１３ａ、１３ｂの周面１４、１４との転がり接触部（トラクション部）で過大な滑りが発生せず、且つ、この転がり接触部の面圧をできるだけ低く抑える事が重要になる。 For this reason, when the pressing force applied to the input side disk 2b constituting the cavity far from the pressing device 24 is lower than the pressing force applied to the input side disk 2a constituting the near side cavity, the toroidal type It becomes difficult to achieve both high transmission efficiency and durability in a continuously variable transmission. The reason for this is as follows. That is, in order to ensure transmission efficiency, rolling contact portions between the input side inner surfaces 3 and 3 and the output side inner surfaces 12 and 12 and the peripheral surfaces 14 and 14 of the power rollers 13a and 13b. It is important that excessive slip does not occur in the (traction part) and that the surface pressure of the rolling contact part is kept as low as possible.

このうち、過大な滑りを抑える為には、伝達トルクの大きさに応じて、上記転がり接触部の面圧を確保する必要がある。この面圧が伝達トルクに対応した適正値よりも小さい場合には、上記転がり接触部で過大な滑りが発生し、伝達効率が悪化するだけでなく、過大な滑りにより局所的に著しい発熱を生じ、油膜切れを起こして著しい摩耗が発生し、耐久性が低下する。これに対して、上記面圧が大き過ぎた場合には、上記転がり接触部での弾性変形量が過大になって転がり抵抗が増大し、伝達効率が悪化するだけでなく、過大な面圧により転がり疲れ寿命が低下し、耐久性も悪化する。この様に、面圧が過小であっても、或は過大であっても、伝達効率と耐久性との双方が悪化するが、悪化の程度は、過小である場合の方が著しい。 Among these, in order to suppress excessive slip, it is necessary to ensure the surface pressure of the rolling contact portion according to the magnitude of the transmission torque. When this surface pressure is smaller than the appropriate value corresponding to the transmission torque, excessive slippage occurs at the rolling contact portion, not only the transmission efficiency is deteriorated, but also excessive heat is generated locally due to the excessive slippage. As a result, the oil film is cut, and significant wear occurs, resulting in a decrease in durability. On the other hand, if the surface pressure is too large, the amount of elastic deformation at the rolling contact portion becomes excessive and the rolling resistance increases, not only the transmission efficiency deteriorates, but also due to the excessive surface pressure. Rolling fatigue life decreases and durability deteriorates. Thus, even if the surface pressure is too low or too high, both transmission efficiency and durability are deteriorated, but the degree of deterioration is more remarkable when it is too low.

この様に、前述の図４〜５に示した従来構造の場合には、両キャビティ同士の間で押圧力に差が生じる。この為、この押圧力が低い側（図４〜５の右側）のキャビティ部分でも、この押圧力（に基づくトラクション部の面圧）が過小にならない様に、前記押圧装置２４が発生する押圧力を設定する必要がある。従って、この押圧装置２４に隣接した、図４〜５の左側のキャビティ部分では、上記押圧力（に基づくトラクション部の面圧）が過大になる。この結果、このキャビティ部分では、前述した理由により、伝達効率及び耐久性が悪化する事が避けられない。押圧装置を各キャビティ毎に設ければ上述の様な問題はなくなるが、コストが嵩むだけでなく、トロイダル型無段変速機全体としての軸方向寸法が嵩み重量が増大する等、実用的な解決手段とは言えない。 Thus, in the case of the conventional structure shown in FIGS. 4 to 5 described above, a difference occurs in the pressing force between the cavities. For this reason, the pressing force generated by the pressing device 24 so that the pressing force (the surface pressure of the traction part based on the pressing force) does not become excessive even in the cavity portion on the side where the pressing force is low (right side in FIGS. 4 to 5). Need to be set. Therefore, in the cavity portion on the left side of FIGS. 4 to 5 adjacent to the pressing device 24, the pressing force (based on the surface pressure of the traction portion) is excessive. As a result, in this cavity part, it is inevitable that transmission efficiency and durability deteriorate for the reason described above. If a pressing device is provided for each cavity, the above-mentioned problems are eliminated. However, not only the cost increases, but the axial dimension of the toroidal continuously variable transmission as a whole increases and the weight increases. It's not a solution.

尚、特許文献４、５には、トロイダル型無段変速機で、各ディスクの内側面と各パワーローラの周面との転がり接触部の位置を工夫する発明が記載されている。但し、上記特許文献４、５に記載された発明は、トルク伝達に伴う各部の弾性変形に拘らず、上記各ディスクの内側面にエッヂロードが加わるのを防止して、トラクション部の耐久性確保を図るものである。以下に詳述する本発明の様に、各ディスクの内側面と各パワーローラの周面との転がり接触部の位置を、押圧装置の設置位置との関係で１対のキャビティ同士の間で異ならせ、ダブルキャビティ型のトロイダル型無段変速機の伝達効率及び耐久性を向上させる事を意図しているものではない。 Patent Documents 4 and 5 describe inventions in which the position of the rolling contact portion between the inner surface of each disk and the peripheral surface of each power roller is devised in a toroidal type continuously variable transmission. However, the inventions described in Patent Documents 4 and 5 prevent the edge load from being applied to the inner surface of each disk and ensure the durability of the traction section, regardless of the elastic deformation of each part accompanying torque transmission. Is intended. As in the present invention described in detail below, the position of the rolling contact portion between the inner surface of each disk and the peripheral surface of each power roller is different between a pair of cavities in relation to the installation position of the pressing device. It is not intended to improve the transmission efficiency and durability of the double cavity type toroidal continuously variable transmission.

特開平２−２８３９４９号公報JP-A-2-283949 特開平６−２８０９５９号公報JP-A-6-280959 特開２００３−３１４６４５号公報JP 2003-314645 A 特開平８−４８６８号公報JP-A-8-4868 特許第３４５８８６１号公報Japanese Patent No. 3458861

本発明は、上述の様な事情に鑑み、押圧装置の設置位置との関係で、トラクション部の面圧を確保する為に加えられる押圧力が異なる場合でも、この面圧に実用上問題となる程の差が生じない様にして、ハーフトロイダル型で、且つ、ダブルキャビティ型のトロイダル型無段変速機の伝達効率及び耐久性を向上させるべく発明したものである。 In view of the above-described circumstances, the present invention has a practical problem with this surface pressure even when the pressing force applied to ensure the surface pressure of the traction portion is different from the installation position of the pressing device. The present invention has been invented to improve the transmission efficiency and durability of a half-toroidal and double-cavity toroidal-type continuously variable transmission so that no significant difference occurs.

本発明のトロイダル型無段変速機は、前述した図４〜６に示す従来構造と同様に、ハーフトロイダル型、且つ、ダブルキャビティ型で、回転軸と、１対の外側ディスクと、内側ディスクと、複数個のトラニオンと、複数個のパワーローラと、押圧装置とを備える。
このうちの回転軸は、ケーシング内に支持されている。
又、上記両外側ディスクは、それぞれが断面円弧形の凹面である互いの軸方向片側面同士を対向させた状態で上記回転軸の軸方向２個所位置に、この回転軸と同期した回転を自在として支持されている。
又、上記内側ディスクは、上記回転軸の中間部周囲に、断面円弧形の凹面である軸方向両側面を上記両外側ディスクの軸方向片側面に対向させた状態で、上記回転軸に対する相対回転を自在に、且つ、この回転軸の軸方向に関する移動を阻止された状態で支持されている。
又、上記各トラニオンは、軸方向に関して上記内側ディスクの軸方向側面と上記両外側ディスクの軸方向片側面との間位置にそれぞれ複数個ずつ、上記回転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自在に設けられたもので、それぞれの両端部に互いに同心の、これら各枢軸を設けている。
又、上記各パワーローラは、上記各トラニオンの中間部にその基半部を枢支すると共に、その先半部をこれら各トラニオンの内側面から突出させた偏心軸のうちの先半部周囲に回転自在に支持され、球状凸面としたそれぞれの周面を、上記内側ディスクの軸方向側面と上記両外側ディスクの軸方向片側面とに転がり接触させている。
又、上記各パワーローラと上記各トラニオンの内側面との間に、これら各パワーローラの側から順番に、これら各パワーローラに加わるスラスト荷重を支承しつつこれら各パワーローラの回転を許容するスラスト玉軸受と、このスラスト玉軸受を構成する外輪が上記各偏心軸の基半部を中心として揺動変位する事を許容する第二のスラスト軸受とを設けている。
更に、上記押圧装置は、上記両外側ディスクのうちの一方の外側ディスクを他方の外側ディスクに向けて押圧する。
特に、本発明のトロイダル型無段変速機に於いては、上記押圧装置から遠い側に存在する各パワーローラの周面と上記各ディスクの側面との接触部の位置を、上記押圧装置に近い側に存在する各パワーローラの周面と上記各ディスクの側面との接触部の位置よりも、これら各ディスクの径方向に関して内側に位置させている。
この為に本発明のトロイダル型無段変速機では、上記押圧装置から遠い側に存在する上記各パワーローラと上記各トラニオンの内側面との間に設ける第二のスラスト軸受の、これら各パワーローラの軸方向に関する寸法を、上記押圧装置に近い側に存在する上記各パワーローラと上記各トラニオンの内側面との間に設ける第二のスラスト軸受の、これら各パワーローラの軸方向に関する寸法よりも大きくしている。 The toroidal type continuously variable transmission of the present invention is a half toroidal type and double cavity type, similar to the conventional structure shown in FIGS. 4 to 6 described above , and includes a rotating shaft, a pair of outer disks, and an inner disk. A plurality of trunnions , a plurality of power rollers, and a pressing device.
Among these, the rotating shaft is supported in the casing.
In addition, the both outer disks rotate in synchronization with the rotation shaft at two axial positions of the rotation shaft in a state in which the respective axial one side surfaces, which are concave surfaces each having an arcuate cross section, are opposed to each other. It is supported as free.
In addition, the inner disk has a relative to the rotating shaft in a state where both axial side surfaces, which are concave surfaces having an arc cross section, are opposed to one axial side surface of the outer disks, around the middle portion of the rotating shaft. It is supported in a state where it can freely rotate and is prevented from moving in the axial direction of the rotating shaft.
Each trunnion is centered on a pivot that is twisted with respect to the rotating shaft, and a plurality of trunnions are arranged in a position between the axial side surface of the inner disk and one axial side surface of the outer disks. These pivots are provided concentrically with each other at both ends .
Each power roller has its base half pivotally supported at the intermediate part of each trunnion, and its tip half protrudes from the inner surface of each trunnion around the front half of the eccentric shaft. Each peripheral surface that is rotatably supported and has a spherical convex surface is brought into rolling contact with the axial side surface of the inner disk and the axial side surfaces of the outer disks.
Further, a thrust that allows rotation of each power roller while supporting the thrust load applied to each power roller in order from the side of each power roller between each power roller and the inner surface of each trunnion. A ball bearing and a second thrust bearing that allows the outer ring constituting the thrust ball bearing to swing and displace about the base half of each eccentric shaft are provided.
Further, the pressing device presses one of the outer disks toward the other outer disk.
In particular, in the toroidal-type continuously variable transmission according to the present invention, the position of the contact portion between the peripheral surface of each power roller and the side surface of each disk located on the side far from the pressing device is close to the pressing device. It is located inside the radial direction of each disk from the position of the contact portion between the peripheral surface of each power roller present on the side and the side surface of each disk.
For this reason, in the toroidal type continuously variable transmission of the present invention, each of these power rollers of the second thrust bearing provided between each of the power rollers existing on the side far from the pressing device and the inner surface of each trunnion. The dimension of the second thrust bearing provided between each of the power rollers present on the side close to the pressing device and the inner surface of each trunnion is larger than the dimensions of the power rollers in the axial direction. It is getting bigger.

上述の様に構成する本発明のトロイダル型無段変速機によれば、押圧装置が発生する押圧力が１対の外側ディスクに伝わる迄の間に存在する、抵抗となる部分の相違により、これら両外側ディスクを内側ディスクに押圧する力が異なっても、各トラクション部の面圧の差を、０乃至は実用上問題ない程度に抑えられる。この結果、これら各トラクション部に加わる面圧を、何れのトラクション部に就いても適正にし、これら各トラクション部に過大な面圧が作用する事を防止して、トロイダル型無段変速機の伝達効率及び耐久性の向上を図れる。
又、本発明のトロイダル型無段変速機の場合には、パワーローラやトラニオン、更には各ディスク等、比較的コストが嵩む部材に関しては、各キャビティ同士の間で同一仕様（同一形状且つ同一寸法）のものを使用できる。この為、構成部材の製造コストの増大を抑えられる。 According to the toroidal type continuously variable transmission of the present invention configured as described above, due to the difference in resistance portions existing until the pressing force generated by the pressing device is transmitted to the pair of outer disks, Even if the forces pressing the both outer disks against the inner disk are different, the difference in surface pressure between the traction portions can be suppressed to zero or practically no problem. As a result, the surface pressure applied to each of these traction sections is made appropriate for any traction section, preventing excessive surface pressure from acting on each of these traction sections, and transmitting the toroidal continuously variable transmission. Efficiency and durability can be improved.
Further, in the case of the toroidal type continuously variable transmission of the present invention, the relatively high cost members such as the power roller, the trunnion, and further each disk have the same specifications (the same shape and the same size) between the cavities. ) Can be used. For this reason, the increase in the manufacturing cost of a structural member can be suppressed.

本発明を実施する場合に好ましくは、請求項２に記載した発明の様に、上記第二のスラスト軸受を、スラストレースと複数のニードルとを備えたスラストニードル軸受とする。そして、上記押圧装置から遠い側に存在するスラストニードル軸受のスラストレースの厚さ寸法を、この押圧装置に近い側に存在するスラストニードル軸受のスラストレースの厚さ寸法よりも大きくする。
この様な構成を採用すれば、単純な形状（単なる平板状）で低コストで造れる部材の厚さを変えるのみで済む為、本発明を最も低コストで実施できる。 When carrying out the present invention, preferably, the second thrust bearing is a thrust needle bearing provided with a thrust trace and a plurality of needles, as in the invention described in claim 2 . Then, the thickness dimension of the thrust trace of the thrust needle bearing existing on the side far from the pressing device is made larger than the thickness dimension of the thrust trace of the thrust needle bearing existing on the side closer to the pressing device.
By adopting such a configuration, it is only necessary to change the thickness of a member that can be manufactured with a simple shape (simple flat plate shape) at low cost, and therefore the present invention can be implemented at the lowest cost.

図１は、本発明の実施例を示している。尚、本実施例の特徴は、押圧装置２４に近い側のキャビティと同じく遠い側のキャビティとで各トラクション部の面圧の差を小さくすべく、これら各トラクション部の位置を、各ディスク２ａ、１１ａ、２ｂ、１１ｂの径方向に関して互いに異ならせた点にある。その他の部分の構造及び作用は、前述の図４〜６に示した従来構造と同様であるから、重複する図示及び説明は省略若しくは簡略にし、以下、本実施例の特徴部分を中心に説明する。 FIG. 1 shows an embodiment of the present invention . The feature of this embodiment is that the position of each traction portion is set to each disk 2a, in order to reduce the difference in surface pressure between each traction portion between the cavity closer to the pressing device 24 and the cavity farther from the cavity. 11a, 2b, and 11b are different from each other in the radial direction. Since the structure and operation of other parts are the same as those of the conventional structure shown in FIGS. 4 to 6 described above, overlapping illustrations and explanations are omitted or simplified, and the following description will focus on the characteristic parts of the present embodiment. .

本実施例の場合、各パワーローラ１３ａ、１３ｂの外側面と各トラニオン１５ａ、１５ｂの内側面との間に、これら各パワーローラ１３ａ、１３ｂの側から順番に、スラスト玉軸受１８、１８とスラストニードル軸受１９ａ、１９ｂとを設けている。このうちのスラスト玉軸受１８、１８は、上記各パワーローラ１３ａ、１３ｂに加わるスラスト荷重を支承しつつ、これら各パワーローラ１３ａ、１３ｂの回転を許容する為のものである。又、上記各スラストニードル軸受１９ａ、１９ｂは、上記各スラスト玉軸受１８、１８を構成する外輪３０、３０が各偏心軸１６、１６の基半部を中心として揺動変位する事を許容する為のものである。以上の構成は、従来から一般的に知られているトロイダル型無段変速機と同様である。 In the case of the present embodiment, the thrust ball bearings 18 and 18 and the thrust are arranged between the outer surfaces of the power rollers 13a and 13b and the inner surfaces of the trunnions 15a and 15b in this order from the power rollers 13a and 13b. Needle bearings 19a and 19b are provided. Among these, the thrust ball bearings 18 and 18 are for allowing the rotation of the power rollers 13a and 13b while supporting the thrust load applied to the power rollers 13a and 13b. The thrust needle bearings 19a and 19b allow the outer rings 30 and 30 constituting the thrust ball bearings 18 and 18 to swing and displace around the base half portions of the eccentric shafts 16 and 16, respectively. belongs to. The above configuration is the same as that of a conventionally known toroidal type continuously variable transmission.

特に、本実施例のトロイダル型無段変速機の場合には、上記各スラストニードル軸受１９ａ、１９ｂの、上記各パワーローラ１３ａ、１３ｂの軸方向（図１〜２の上下方向）に関する厚さ寸法を、１対のキャビティ同士の間で、互いに異ならせている。具体的には、押圧装置２４から遠い側（図１の右側）に存在する各パワーローラ１３ｂ、１３ｂと各トラニオン１５ｂ、１５ｂの内側面との間に設ける各スラストニードル軸受１９ｂ、１９ｂの厚さ寸法Ｔ_b を、上記押圧装置２４に近い側（図１の左側）に存在する各パワーローラ１３ａ、１３ａと各トラニオン１５ａ、１５ａの内側面との間に設ける各スラストニードル軸受１９ａ、１９ａの厚さ寸法Ｔ_a よりも大きく（Ｔ_b ＞Ｔ_a ）している。この為に本実施例の場合には、上記押圧装置２４から遠い側に存在するスラストニードル軸受１９ｂを構成するスラストレース３１ｂの厚さ寸法ｔ_b を、上記押圧装置２４に近い側に存在するスラストニードル軸受１９ａを構成するスラストレース３１ａの厚さ寸法ｔ_a よりも大きく（ｔ_b ＞ｔ_a ）している。 In particular, in the case of the toroidal type continuously variable transmission of the present embodiment, the thickness dimension of the thrust needle bearings 19a and 19b in the axial direction of the power rollers 13a and 13b (vertical direction in FIGS. 1 and 2). Are different from each other between a pair of cavities. Specifically, the thickness of each thrust needle bearing 19b, 19b provided between each power roller 13b, 13b existing on the side far from the pressing device 24 (right side in FIG. 1) and the inner surface of each trunnion 15b, 15b. the dimension T _b, the thickness of the thrust needle bearings 19a, 19a provided between said pressure device power rollers 13a present on the side (left side in FIG. 1) close to 24, 13a and the respective trunnions 15a, 15a inner surface of It is larger than the length dimension T _a (T _b > T _a ). In the case of the embodiment in this order, thrust the thickness t _b of the thrust race 31b constituting the thrust needle bearing 19b which is present on the far side from the pressing device 24, present on the side closer to the pressing device 24 greater than the thickness t _a of the thrust races 31a constituting the needle bearing 19a is (t _b> t _a).

他の部材、即ち、前記各入力側ディスク２ａ、２ｂ、前記各出力側ディスク１１ａ、１１ｂ、上記各パワーローラ１３ａ、１３ｂ、上記各トラニオン１５ａ、１５ｂの形状及び寸法は、１対のキャビティ同士の間で、互いに同じとしている。従って、上記各スラストレース３１ａ、３１ｂの厚さ寸法ｔ_a 、ｔ_b を上述の様に規制する事に伴い、上記各パワーローラ１３ａ、１３ｂの周面１４、１４と上記両入力側ディスク２ａ、２ｂの入力側内側面３、３及び上記両出力側ディスク１１ａ、１１ｂの出力側内側面１２、１２との転がり接触位置が、上記両キャビティ同士の間で互いに異なる。具体的には、上記押圧装置２４から遠い側に存在する上記各パワーローラ１３ｂ、１３ｂの周面１４、１４と上記入力側ディスク２ｂの入力側内側面３及び上記出力側ディスク１１ｂの出力側内側面１２との接触部の位置（図１〜２のα点）を、上記押圧装置２４に近い側に存在する上記各パワーローラ１３ａ、１３ａの周面１４、１４と上記入力側ディスク２ａの入力側内側面３及び上記出力側ディスク１１ａの出力側内側面１２との接触部の位置（図１〜２のβ点）よりも、これら各ディスク２ａ、２ｂ、１１ａ、１１ｂの径方向に関して、図１〜２のδ分だけ、内側に（入力回転軸１の近くに）位置させている。 The shapes and dimensions of the other members, that is, the input disks 2a and 2b, the output disks 11a and 11b, the power rollers 13a and 13b, and the trunnions 15a and 15b are the same as each other. They are the same as each other. Accordingly, as the thickness dimensions t _a and t _b of the thrust races 31a and 31b are regulated as described above, the peripheral surfaces 14 and 14 of the power rollers 13a and 13b and the input side disks 2a, The rolling contact positions of the input side inner surfaces 3 and 3 of 2b and the output side inner surfaces 12 and 12 of the output side disks 11a and 11b are different from each other between the cavities. Specifically, the peripheral surfaces 14, 14 of the power rollers 13b, 13b existing on the side far from the pressing device 24, the input side inner surface 3 of the input side disk 2b, and the output side inner side of the output side disk 11b. The position of the contact portion with the side surface 12 (α point in FIGS. 1 and 2) is input to the peripheral surfaces 14 and 14 of the power rollers 13 a and 13 a existing on the side close to the pressing device 24 and the input side disk 2 a. With respect to the radial direction of each of these disks 2a, 2b, 11a, and 11b, rather than the position of the contact portion between the side inner surface 3 and the output side inner surface 12 of the output side disk 11a (β point in FIGS. 1 and 2). It is located inward (near the input rotation shaft 1) by δ of 1 to 2.

上述の様に構成する本実施例のトロイダル型無段変速機によれば、上記押圧装置２４が発生する押圧力が１対の入力側ディスク２ａ、２ｂに伝わる迄の間に存在する、抵抗となる部分の相違により、これら両入力側ディスク２ａ、２ｂを上記両出力側ディスク１１ａ、１１ｂに押圧する力が異なっても、各トラクション部の面圧の差を、０乃至は実用上問題ない程度に抑えられる。この結果、これら各トラクション部に加わる面圧を、何れのトラクション部に就いても適正にし、これら各トラクション部に過大な面圧が作用する事を防止して、トロイダル型無段変速機の伝達効率及び耐久性の向上を図れる。 According to the toroidal type continuously variable transmission of the present embodiment configured as described above, the resistance existing between the time when the pressing force generated by the pressing device 24 is transmitted to the pair of input side disks 2a, 2b, Even if the force pressing these two input-side disks 2a, 2b against the two output-side disks 11a, 11b is different, the difference in surface pressure between the traction sections is 0 or so that there is no practical problem. Can be suppressed. As a result, the surface pressure applied to each of these traction sections is made appropriate for any traction section, preventing excessive surface pressure from acting on each of these traction sections, and transmitting the toroidal continuously variable transmission. Efficiency and durability can be improved.

尚、上記各トラクション部（接触点）を上記入力回転軸１の近くに位置させると、接触点の開き角θは小さくなる。即ち、図２に示す様に、上記押圧装置２４に近い側のキャビティ内のパワーローラ１３ａに関する開き角θ_a が、遠い側のキャビティ内のパワーローラ１３ｂに関する開き角θ_b よりも大きく（θ_a ＞θ_b ）なる。この様に１対のキャビティ同士の間で開き角θが異なると、同じ変速比を実現する為の傾転角φも異なり（開き角θが小さくなる程傾転角φも小さくなり）、変速動作の為に各トラニオン１５ａ、１５ｂを枢軸２１、２１（図６参照）を中心に揺動変位させる揺動角度も異なる（開き角θが小さくなる程揺動角度が大きくなる）。但し、この様な、両キャビティ同士の間で変速比を互いに一致させる為、揺動角度を互いに異ならせる調節は、容易に行なえる。 When each traction portion (contact point) is positioned near the input rotation shaft 1, the opening angle θ of the contact point is reduced. That is, as shown in FIG. 2, the pressing device opening angle theta _a related power roller 13a in the side of the cavity close to 24 is larger than the opening angle theta _b about power roller 13b in the far side of the cavity (theta _a > Θ _b ). Thus, when the opening angle θ is different between a pair of cavities, the tilt angle φ for realizing the same gear ratio is also different (the smaller the opening angle θ is, the smaller the tilt angle φ is). The swing angles at which the trunnions 15a and 15b are swung about the pivots 21 and 21 (see FIG. 6) for operation are different (the swing angle increases as the opening angle θ decreases). However, in order to make the transmission ratios between the two cavities coincide with each other, the adjustment for making the swing angles different from each other can be easily performed.

そこで、入力回転軸１の軸方向に関する押圧力の相違に拘らず、上記各トラクション部の面圧を均一にできる理由に就いて、図３を参照しつつ説明する。上記押圧装置２４が発生する押圧力をＦａとし、各キャビティ毎のパワーローラの数（図示の例では２）をｎとした場合、トラクション部の面圧（接触面押し付け力）Ｆｃは、次の（１）式で表される。
Ｆｃ＝（Ｆａ／ｎ）／ sinφ −−− （１）
で表せる。
一方、上記入力回転軸１に入力されるトルクをＴ_inとし、トラクション係数をμとし、入力側内側面３に関するトラクション部の公転半径をｒ₁ とし、各トラクション部で伝達する力をＦｔとした場合、次の（２）式が成り立つ。
Ｔ_in＝ｎ・ｒ₁ ・Ｆｔ＝ｎ・ｒ₁ ・μ・Ｆｃ −−− （２）
これら（１）（２）式からＦｃを消去すると、次の（３）式を得られる。
Ｆａ＝（Ｔ_in・ sinφ）／（ｒ₁ ・μ） −−− （３）
又、前記入力側ディスク２ａ、２ｂの描く仮想最小長さｅ₀ をキャビティ半径Ｒ₁₂で除す事により得られるアスペクト比をｋ₀ とすると、上記公転半径ｒ₁ は、次の（４）式で求められる。
ｒ₁ ＝Ｒ₁₂（１＋ｋ₀ −cos φ） −−− （４）
上記（３）式に、この（４）式とアスペクト比ｋ₀ を代入すると、次の（５）式を得られる。
Ｆａ＝（Ｔ_in・ sinφ）／｛μ・Ｒ₁₂（１＋ｋ₀ −cos φ）｝ −−− （５）
更に、この（５）式を上記（１）式に代入して、次の（６）式を得られる。
Ｆｃ＝Ｔ_in／ｎ・｛μ・Ｒ₁₂（１＋ｋ₀ − cosφ）｝ −−− （６） Therefore, the reason why the surface pressure of each traction portion can be made uniform regardless of the difference in the pressing force in the axial direction of the input rotary shaft 1 will be described with reference to FIG. When the pressing force generated by the pressing device 24 is Fa and the number of power rollers for each cavity (2 in the illustrated example) is n, the surface pressure (contact surface pressing force) Fc of the traction portion is It is represented by the formula (1).
Fc = (Fa / n) / sinφ −−− (1)
It can be expressed as
On the other hand, the torque input to the input rotating shaft 1 is T _in , the traction coefficient is μ, the revolution radius of the traction portion with respect to the input side inner surface 3 is r _1, and the force transmitted by each traction portion is Ft. In this case, the following equation (2) holds.
T _in = n · r ₁ · Ft = n · r ₁ · μ · Fc (2)
When Fc is deleted from these equations (1) and (2), the following equation (3) is obtained.
_{Fa = (T in · sinφ)} / (r 1 · μ) --- (3)
When the aspect ratio obtained by dividing the virtual minimum length e ₀ drawn by the input side disks 2a, 2b by the cavity radius R ₁₂ is k ₀ , the revolution radius r ₁ is given by the following equation (4). Is required.
r ₁ = R ₁₂ (1 + k ₀ −cos φ) −−− (4)
Substituting this equation (4) and the aspect ratio k ₀ into the above equation (3), the following equation (5) is obtained.
Fa = (T _in · sin φ) / {μ · R ₁₂ (1 + k ₀ −cos φ)} (5)
Further, by substituting this equation (5) into the above equation (1), the following equation (6) can be obtained.
Fc = T _in / n · {μ · R ₁₂ (1 + k ₀ −cosφ)} −−− (6)

ハーフトロイダル型無段変速機の場合には、傾転角φは１８０度未満（０＜φ＜１８０度）であり、 cosφは減少関数である。即ち、上記各トラクション部が上記入力回転軸１に近付き、上記傾転角φが小さくなる程、トラクション部の面圧（接触面押し付け力）Ｆｃは大きくなる。従って、前記押圧装置２４が発生する押圧力Ｆａが出力側ディスク１１ｂに伝わる迄の経路の途中に多くの抵抗が存在する為に押圧力Ｆａが小さくなる、上記押圧装置２４から遠い側のキャビティ部分で、上記各トラクション部を上記入力回転軸１に近付ければ、この入力回転軸１の軸方向に関する押圧力の相違に拘らず、上記各トラクション部の面圧を均一にできる。 In the case of a half-toroidal continuously variable transmission, the tilt angle φ is less than 180 degrees (0 <φ <180 degrees), and cos φ is a decreasing function. That is, the surface pressure (contact surface pressing force) Fc of the traction portion increases as the traction portions approach the input rotation shaft 1 and the tilt angle φ decreases. Therefore, since there is a lot of resistance in the path until the pressing force Fa generated by the pressing device 24 is transmitted to the output side disk 11b, the pressing force Fa becomes small. Thus, when the traction portions are brought close to the input rotation shaft 1, the surface pressure of the traction portions can be made uniform regardless of the difference in the pressing force in the axial direction of the input rotation shaft 1.

尚、内側ディスクである出力側ディスク１１ａ、１１ｂは、図示の様に、互いに独立したものを出力筒８により連結したものであっても良いが、１対の出力側ディスクの外側面同士を突き合わせた如き、一体型の構造でも良い。この様な一体型の出力側ディスクを軸方向に関する移動を阻止された状態で支持する為には、例えば前述の特許文献３に記載された構造を採用できる。又、トラクション部の面圧を確保する為の押圧装置にしても、図示の様なローディングカム式のものに限らず、上記特許文献３に記載された様な油圧式のものも採用できる。更には、上記押圧装置２４から遠い側のキャビティ部分で、上記各トラクション部を上記入力回転軸１に近付ける為の構造は、図示の構造に限定されない。例えば、各スラストニードル軸受を構成するニードルの径を異ならせたり、各スラスト玉軸受を構成する玉の直径を異ならせたり、更にはパワーローラや各ディスク、或は各トラニオンの寸法、形状を異ならせたりして、上記各トラクション部の位置を調節する事もできる。 The output side disks 11a and 11b, which are the inner side disks, may be connected to each other by the output cylinder 8 as shown in the figure, but the outer surfaces of the pair of output side disks are butted together. For example, an integral structure may be used. In order to support such an integrated output-side disk in a state in which movement in the axial direction is prevented, the structure described in Patent Document 3, for example, can be employed. Further, the pressing device for securing the surface pressure of the traction portion is not limited to the loading cam type as shown in the figure, and a hydraulic type as described in Patent Document 3 can also be adopted. Furthermore, the structure for bringing the traction portions closer to the input rotating shaft 1 at the cavity portion far from the pressing device 24 is not limited to the illustrated structure. For example, the diameter of the needle constituting each thrust needle bearing is varied, the diameter of the ball constituting each thrust ball bearing is varied, and the size and shape of the power roller, each disk, or each trunnion are varied. It is possible to adjust the position of each traction section.

本発明の実施例を示す、図５と同様の断面図。Sectional drawing similar to FIG. 5 which shows the Example of this invention. 各パワーローラの周面と各ディスクの側面との転がり接触部の位置を異ならせる状態を説明する為、両キャビティに組み込んだパワーローラを、中立位置で半分ずつ組み合わせた状態で示す断面図。Sectional drawing which shows the state which combined the power roller incorporated in both the cavities by half in the neutral position, in order to demonstrate the state which changes the position of the rolling contact part of the surrounding surface of each power roller, and the side surface of each disk. 上記転がり接触部の位置を変える事で押圧力を調節できる理由を説明する為の模式図。The schematic diagram for demonstrating the reason which pressing force can be adjusted by changing the position of the said rolling contact part. 従来構造の第１例を示す断面図。Sectional drawing which shows the 1st example of a conventional structure. 図４のＡ−Ａ断面図。AA sectional drawing of FIG. 同Ｂ−Ｂ断面図。BB sectional drawing.

Explanation of symbols

１入力回転軸
２ａ、２ｂ入力側ディスク
３入力側内側面
４ボールスプライン
５ケーシング
６隔壁部
７通孔
８出力筒
９転がり軸受
１０出力歯車
１１ａ、１１ｂ出力側ディスク
１２出力側内側面
１３ａ、１３ｂパワーローラ
１４周面
１５ａ、１５ｂトラニオン
１６偏心軸
１７ラジアルニードル軸受
１８スラスト玉軸受
１９、１９ａ、１９ｂスラストニードル軸受
２０ラジアルニードル軸受
２１枢軸
２２アクチェータ
２３駆動軸
２４押圧装置
２５カム板
２６凹凸係合部
２７ブッシュ
２８ラジアルニードル軸受
２９ラジアルニードル軸受
３０外輪
３１ａ、３１ｂスラストレース DESCRIPTION OF SYMBOLS 1 Input rotating shaft 2a, 2b Input side disk 3 Input side inner surface 4 Ball spline 5 Casing 6 Bulkhead part 7 Through-hole 8 Output cylinder 9 Rolling bearing 10 Output gear 11a, 11b Output side disk 12 Output side inner surface 13a, 13b Power Roller 14 Peripheral surface 15a, 15b Trunnion 16 Eccentric shaft 17 Radial needle bearing 18 Thrust ball bearing 19, 19a, 19b Thrust needle bearing 20 Radial needle bearing 21 Pivot 22 Actuator 23 Drive shaft 24 Pressing device 25 Cam plate 26 Uneven engaging part 27 Bush 28 Radial needle bearing 29 Radial needle bearing 30 Outer ring 31a, 31b Thrust trace

Claims

The rotary shaft supported in the casing and the respective one side surfaces in the axial direction, each of which is a concave surface having an arc cross section, are synchronized with the rotary shaft at two axial positions of the rotary shaft. A pair of outer disks that are supported for rotation, and an axial side surface that is a concave surface having an arc cross section around the middle part of the rotating shaft is opposed to one axial side surface of both outer disks. The inner disk supported in a state of being freely rotatable relative to the rotating shaft and prevented from moving in the axial direction of the rotating shaft, the axial side surface of the inner disk with respect to the axial direction, and the both outer disks. A plurality of pivots that are concentric with each other at both ends, each having a plurality of pivotal displacements around a pivot that is twisted with respect to the rotary shaft, each being located in a position between one side surface in the axial direction. Set up And trunnion and rotatably supported these intermediate portions of the trunnions with pivotally supports the base half portion, the previously halves around earlier half portion of the eccentric shaft which projects from the inner surface of the trunnions And a power roller in which each circumferential surface formed as a spherical convex surface is brought into rolling contact with the axial side surface of the inner disk and the axial side surface of both outer disks, and one outer disk of the both outer disks. A thrust device that presses the second outer disk toward the other outer disk, and a thrust load applied to each of the power rollers in order from the power roller side between the power rollers and the inner surface of the trunnion. The thrust ball bearing that allows the rotation of each of the power rollers while supporting the shaft, and the outer ring that constitutes the thrust ball bearing swings about the base half of each of the eccentric shafts Provided a second thrust bearing that allows ordinating that, in the half-toroidal type continuously variable transmission, the inner surfaces of the power rollers and the trunnions present on the far side from the pressing device The second thrust bearing provided between the second roller and the second roller is provided with a dimension in the axial direction of each of the power rollers between the power rollers existing on the side close to the pressing device and the inner surface of the trunnions. of the thrust bearing, by greater than the dimension in the axial direction of the power rollers, the position of the contact portion between the peripheral surface and the side surfaces of each disc of the power rollers present on the far side from the pressing device , than the position of the contact portion between the peripheral surface and the side surfaces of each disc of the power rollers present on the side closer to the pressing device, inside in the radial direction of the disk A toroidal-type continuously variable transmission characterized by being located in

The second thrust bearing is a thrust needle bearing having a thrust trace and a plurality of needles, and the thickness dimension of the thrust trace of the thrust needle bearing existing on the side far from the pressing device is closer to the pressing device. The toroidal-type continuously variable transmission according to claim 1 , wherein the toroidal-type continuously variable transmission is larger than a thickness dimension of a thrust trace of an existing thrust needle bearing.