JP3702598B2 - Half toroidal continuously variable transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a half-toroidal continuously variable transmission used as a transmission for an automobile, for example.
[0002]
[Prior art]
For example, a continuous transmission device used as a transmission for an automobile is known from, for example, Japanese Patent Publication No. 6-21625. The continuous transmission device includes a toroidal continuously variable transmission in which a power roller is tiltably contacted between an input disk and an output disk, and a planetary gear mechanism connected to the output disk. .
[0003]
Then, an input is received from an input shaft that is rotationally driven by the engine, and power is output to the output shaft. The planetary gear mechanism has a sun gear driven by an input shaft and a planet carrier driven by an output disk, and is driven by an output shaft connected to a ring gear.
[0004]
The continuous transmission device disclosed in Japanese Patent Publication No. 6-21625 includes a first planetary gear mechanism and a second planetary gear mechanism. The planetary carrier of the first planetary gear mechanism and the sun gear of the second planetary gear mechanism are driven by the output shaft of the continuous transmission, and the sun gear and the second planetary gear mechanism of the first planetary gear mechanism are driven. Are driven by the engine, the ring gear of the first planetary gear mechanism is a low speed output unit, and the planet carrier of the second planetary gear mechanism is a high speed output unit.
[0005]
[Problems to be solved by the invention]
However, since the conventional continuous transmission device is a full toroidal continuously variable transmission, the power loss is large at the contact surface between the input disk and the power roller that is slidably contacted between the output disk and the power disk. There was a problem of poor transmission efficiency.
[0006]
The present invention has been made paying attention to the above circumstances, and an object thereof is to provide a half-toroidal continuously variable transmission capable of improving power transmission efficiency.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an input shaft that is rotationally driven by a drive source, an output shaft that extracts power based on the rotation of the input shaft, the input shaft, and the output shaft. A variator and a planetary gear mechanism disposed between the pair of opposed input disks rotating in conjunction with the input shaft and coaxially disposed between the pair of input disks. A pair of output disks that rotate in synchronism with each other, an output gear that rotates together with these output disks, a power transmission shaft that connects the pair of input disks, and a tilt between the input disk and the output disk The planetary gear mechanism includes a sun gear, a ring gear disposed around the sun gear, and the sun gear and the ring gear. A toroidal type continuously variable transmission comprising a plurality of planet gears rotatably supported by Yaria, said output shaft and is coaxially with the central axis of the input shaft and the power transmission shaft said planetary gear mechanism And a hydraulic pressure pressing mechanism that presses the input disk toward the power roller and the output disk in the axial direction, and a countershaft that rotates the output gear and the sun gear together, A first power transmission including the counter shaft for transmitting the rotation of the disk to the sun gear of the planetary gear mechanism through the counter shaft and for circulating the rotation of the sun gear of the planetary gear mechanism to the variator. mechanism and a second power including the power transmission shaft and the central shaft for transmitting the rotation of the input disk to the carrier of the planetary gear mechanism Characterized in that it was and a reach mechanism.
A second aspect is characterized in that, in the first aspect, the hydraulic pressing mechanism is provided on the input shaft.
A third aspect is characterized in that, in the first aspect, the hydraulic pressure pressing mechanism is provided on the output disk side.
A fourth aspect of the present invention is characterized in that , in the first aspect , the planetary gear mechanism includes first and second planetary gear mechanisms.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0009]
FIG. 1 is a system diagram of a double cavity half-toroidal continuously variable transmission according to a first embodiment. In FIG. 1, reference numeral 1 denotes a toroidal continuously variable transmission, which includes a variator 2 and a planetary gear mechanism 3. The variator 2 includes an input shaft 5 that is rotatably supported by a fixed portion via a bearing or the like, and one end side of which is connected to a drive source 4 such as an engine.
[0010]
The input shaft 5 is provided with a hydraulic piston 6 as a hydraulic pressing mechanism. Power is transmitted to the variator 2 through the hydraulic piston 6. The variator 2 is provided with a power transmission shaft 7 that rotates in conjunction with the hydraulic piston 6. The power transmission shaft 7 is provided with a pair of input disks 8a and 8b opposite to each other. A pair of loosely fitted output disks 9a and 9b are arranged coaxially with respect to the power transmission shaft 7 and rotate in synchronization with each other.
[0011]
The power transmission shaft 7 protrudes rearward from the input disk 8 b constituting the variator 2, and a low speed clutch 28 is provided in the middle of the power transmission shaft 7. In addition, a plurality of power rollers 10 that are in rolling contact with each other are provided between the input disks 8a and 8b and the output disks 9a and 9b. The output disks 9 a and 9 b are connected via a loosely fitted shaft 11 that is loosely fitted to the power transmission shaft 7.
[0012]
In the variator 2, the rotational driving force transmitted to the power transmission shaft 7 is transmitted to the loose fitting shaft 11 via the input disks 8a and 8b, the power roller 10 and the output disks 9a and 9b, and the speed ratio, that is, the output disk 9a, A value obtained by dividing the rotational speed of 9b by the rotational speed of the input disks 8a and 8b is determined by the tilt angle of the power roller 10.
[0013]
That is, when the power roller 10 is in a horizontal state, the speed ratio becomes a neutral state of 1, and when the output disks 9a and 9b side of each power roller 10 is tilted away from the power transmission shaft 7, a corresponding change is made. When the speed ratio decreases and, conversely, when the output disks 9a and 9b of the power rollers 10 tilt in the direction approaching the power transmission shaft 7, the speed ratio increases accordingly. A first gear 12 is fitted to the loose fitting shaft 11, and the first gear 12 meshes with a second gear 13 provided on the counter shaft 14. A third gear 15 is provided at the other end of the counter shaft 14, and the third gear 15 meshes with the fifth gear 17 via the fourth gear 16, and interlocks with the planetary gear mechanism 3. ing.
[0014]
The planetary gear mechanism 3 includes a sun gear 22, a plurality of planetary gears 23 that mesh with the sun gear 22, a carrier 24 that links the planetary gears 23, and a ring gear 25 that meshes with the planetary gear 23. 22 is connected to the fifth gear 17, and the carrier 24 is connected to the low speed clutch 28 via the center shaft 26. The ring gear 25 is provided with an output shaft 27. Further, a high-speed clutch 29 that contacts and separates the ring gear 25 and the carrier 24 of the planetary gear mechanism 3 is provided.
[0015]
Next, the operation of the above-described first embodiment will be described.
[0016]
First, when the low speed clutch 28 is connected and the high speed clutch 29 is released, the power transmission shaft 7 and the central shaft 26 are connected. Accordingly, the rotation of the input shaft 5 is transmitted through the power transmission shaft 7 → the low speed clutch 28 → the central shaft 26 → the carrier 24 of the planetary gear mechanism 3 and the hydraulic piston 6 → the input disks 8a and 8b → the power low 10 → Output disk 9a, 9b → first gear 12 → second gear 13 → counter shaft 14 → third gear 15 → fourth gear 16 → fifth gear 17 → transmitted to the sun gear 22 of the planetary gear mechanism 3 Are transmitted to the planetary gear mechanism 3 through two paths, and an infinite gear ratio is obtained by combining with the variator 2 using the differential of the planetary gear mechanism 3.
[0017]
At this time, if the relative speed between the rotating sun gear 22 and the carrier 24 is “0”, the output rotational speed is “0”. That is, it is possible to start the vehicle from a stopped state without requiring a starting clutch, and to start and reverse by changing the relative speed.
[0018]
On the other hand, when the variator 2 is tilted in the speed increasing side, that is, the power roller 10 in the direction in which the output disks 9a and 9b approach the power transmission shaft 7, the rotational speed of the counter shaft 14 increases according to the tilting, Along with this, the rotational speed of the sun gear 22 of the planetary gear mechanism 3 increases and the rotational speed of the output shaft 27 increases.
[0019]
When the speed change operation as described above is performed, power is circulated from the sun gear 22 at low speed and from the carrier 24 at reverse. That is, the circulating torque at low speed is divided into the first circulating torque and the second circulating torque in the variator 2 after entering the first gear 12. The first circulating torque is transmitted through the path of output disk 9a → power roller 10 → input disk 8a → hydraulic piston 6 → input shaft 5, while the second circulating torque is output disk 9b → power roller 10 → input disk 8b. The power is transmitted through the path of the power transmission shaft 7 → the hydraulic piston 6 → the input shaft 5.
[0020]
In this way, torque is applied to the variator 2 from the output disks 9a, 9b to the input disks 8a, 8b, not from the input disks 8a, 8b. Although there is an effect on the efficiency of the variator 2, the use of the half toroidal type reduces the spin loss on the contact surface and can improve the transmission efficiency.
[0021]
Next, when the high speed clutch 29 is connected and the low speed clutch 28 is released, the input shaft 5 rotates through the output disks 9a and 9b so that the loosely fitted shaft 11 rotates, and the first gear 12 and the second gear Power is transmitted to the gear 13, the counter shaft 14 rotates, and the rotation of the counter shaft 14 is transmitted to the sun gear 22 of the planetary gear mechanism 3 through the third gear 15, the fourth gear 16, and the fifth gear 17. Is done.
[0022]
The rotation of the sun gear 22 is transmitted to the ring gear 25 through the planetary gear 23 and is transmitted to the output shaft 27. Accordingly, the input shaft 5 is directly connected to the output shaft 27, and while maintaining this state, the variator 2 is tilted in the direction in which the speed increasing side, that is, the power roller 10 approaches the power transmission shaft 7 on the output disk 9a, 9b side. When rotating, the rotational speed of the counter shaft 14 is increased in accordance with the tilt, and accordingly, the rotational speed of the sun gear 22 of the planetary gear mechanism 3 is increased and the rotational speed of the output shaft 27 is increased. The speed ratio of the entire continuously variable transmission 1 increases.
[0023]
FIG. 2 shows a second embodiment, in which a hydraulic piston 6 as a hydraulic pressing mechanism is provided on the output disk 9a, 9b side of the variator 2, and the other configuration is the same as that of the first embodiment. The description is omitted.
[0024]
FIG. 3 shows a third embodiment. A half-toroidal continuously variable transmission including a variator 2 and first and second planetary gear mechanisms 3a and 3b between an input shaft 5 and an output shaft 27. Indicates. In FIG. 3, reference numeral 1 denotes a toroidal continuously variable transmission, which includes a variator 2 and first and second planetary gear mechanisms 3a and 3b. The variator 2 includes an input shaft 5 that is rotatably supported by a fixed portion via a bearing or the like, and one end side of which is connected to a drive source 4 such as an engine.
[0025]
The input shaft 5 is provided with a hydraulic piston 6 as a hydraulic pressing mechanism. Power is transmitted to the variator 2 through the hydraulic piston 6. The variator 2 is provided with a power transmission shaft 7 that rotates in conjunction with the hydraulic piston 6. The power transmission shaft 7 is provided with a pair of input disks 8a and 8b opposite to each other. A pair of loosely fitted output disks 9a and 9b are arranged coaxially with respect to the power transmission shaft 7 and rotate in synchronization with each other.
[0026]
The power transmission shaft 7 protrudes rearward from the input disk 8b constituting the variator 2, and this power transmission shaft 7 is connected to the first planetary gear mechanism 3a. In addition, a plurality of power rollers 10 that are in rolling contact with each other are provided between the input disks 8a and 8b and the output disks 9a and 9b. The output disks 9 a and 9 b are connected via a loosely fitted shaft 11 that is loosely fitted to the power transmission shaft 7.
[0027]
In the variator 2, the rotational driving force transmitted to the power transmission shaft 7 is transmitted to the loose fitting shaft 11 via the input disks 8a and 8b, the power roller 10 and the output disks 9a and 9b, and the speed ratio, that is, the output disk 9a, A value obtained by dividing the rotational speed of 9b by the rotational speed of the input disks 8a and 8b is determined by the tilt angle of the power roller 10.
[0028]
That is, when the power roller 10 is in a horizontal state, the speed ratio becomes a neutral state of 1, and when the output disks 9a and 9b side of each power roller 10 is tilted away from the power transmission shaft 7, a corresponding change is made. When the speed ratio decreases and, conversely, when the output disks 9a and 9b of the power rollers 10 tilt in the direction approaching the power transmission shaft 7, the speed ratio increases accordingly. A first gear 12 is fitted to the loose fitting shaft 11, and the first gear 12 meshes with a second gear 13 provided on the counter shaft 14. A third gear 15 is provided at the other end of the counter shaft 14, and the third gear 15 meshes with the fifth gear 17 via the fourth gear 16, and the second planetary gear mechanism 3b. It is linked with.
[0029]
The first planetary gear mechanism 3 a includes a sun gear 18, a plurality of planetary gears 19 that mesh with the sun gear 18, a carrier 20 that links the planetary gears 19, and a ring gear 21 that meshes with the planetary gears 19. The sun gear 18 is connected to the power transmission shaft 7.
[0030]
The second planetary gear mechanism 3 b includes a sun gear 22, a plurality of planetary gears 23 that mesh with the sun gear 22, a carrier 24 that links the planetary gears 23, and a ring gear 25 that meshes with the planetary gears 23. The sun gear 22 is connected to the fifth gear 17, and the carrier 24 is connected to the carrier 20 of the first planetary gear mechanism 3 a via the center shaft 26. The ring gear 25 is provided with an output shaft 27.
[0031]
Further, a low speed clutch 28 for restricting and releasing the rotation of the ring gear 21 is provided between the ring gear 21 and the fixed portion of the first planetary gear mechanism 3a, and the ring gear 25 of the second planetary gear mechanism 3b. A high-speed clutch 29 is provided between the carrier 24 and the carrier 24.
[0032]
Next, the operation of the above-described third embodiment will be described.
[0033]
First, when the low speed clutch 28 is connected and the high speed clutch 29 is released, the ring gear 21 of the first planetary gear mechanism 3 a is fixed, and the rotation of the sun gear 18 is transmitted to the carrier 20 via the planetary gear 19. Then, the rotation of the central shaft 26 is transmitted to the carrier 24 of the second planetary gear mechanism 3b, and is transmitted to the ring gear 25 as a relative speed of rotation of the rotating sun gear 22.
[0034]
Therefore, first, when the low speed clutch 28 is connected and the high speed clutch 29 is released, the rotation of the input shaft 5 causes the power transmission shaft 7 → the sun gear 18 of the first planetary gear mechanism 3 a → the planetary gear 19 → the carrier 20. → Center shaft 26 → path to transmit to carrier 24 of second planetary gear mechanism 3b, hydraulic piston 6 → input disks 8a, 8b → power low 10 → output disks 9a, 9b → first gear 12 → second The second planet by two paths: the gear 13 → the counter shaft 14 → the third gear 15 → the fourth gear 16 → the fifth gear 17 → the path that transmits to the sun gear 22 of the second planetary gear mechanism 3b. The transmission is transmitted to the gear mechanism 3b, and an infinite gear ratio is obtained by combining with the variator 2 using the differential of the second planetary gear mechanism 3b.
[0035]
At this time, if the relative speed between the rotating sun gear 22 and the carrier 24 is “0”, the output rotational speed is “0”. That is, it is possible to start the vehicle from a stopped state without requiring a starting clutch, and to start and reverse by changing the relative speed.
[0036]
On the other hand, when the variator 2 is tilted in the speed increasing side, that is, the power roller 10 in the direction in which the output disks 9a and 9b approach the power transmission shaft 7, the rotational speed of the counter shaft 14 increases according to the tilting, Along with this, the rotational speed of the sun gear 22 of the second planetary gear mechanism 3b increases and the rotational speed of the output shaft 27 increases.
[0037]
When the speed change operation as described above is performed, power is circulated from the sun gear 22 at low speed and from the carrier 24 at reverse. That is, the circulating torque at low speed is divided into the first circulating torque and the second circulating torque in the variator 2 after entering the first gear 12. The first circulating torque is transmitted through the path of output disk 9a → power roller 10 → input disk 8a → hydraulic piston 6 → input shaft 5, while the second circulating torque is output disk 9b → power roller 10 → input disk 8b. The power is transmitted through the path of the power transmission shaft 7 → the hydraulic piston 6 → the input shaft 5.
[0038]
When the speed change operation as described above is performed, power is circulated from the sun gear 22 at low speed and from the carrier 24 at reverse, and the input disk 8a, from the output disks 9a, 9b to the variator 2 instead of from the input disks 8a, 8b. Although a so-called power circulation state is applied where torque is applied to 8b, a large torque is applied to the variator 2 at low speeds in the Ganytral, but by using the half toroidal type, the spin loss at the contact surface is small and the transmission efficiency is improved. be able to.
[0039]
Next, when the high speed clutch 29 is connected and the low speed clutch 28 is released, the input shaft 5 rotates through the output disks 9a and 9b so that the loosely fitted shaft 11 rotates, and the first gear 12 and the second gear Power is transmitted to the gear 13 and the counter shaft 14 rotates. The counter shaft 14 rotates through the third gear 15, the fourth gear 16, and the fifth gear 17, and the sun gear of the second planetary gear mechanism 3 b. 22 is transmitted.
[0040]
The rotation of the sun gear 22 is transmitted to the ring gear 25 through the planetary gear 23 and is transmitted to the output shaft 27. Accordingly, the input shaft 5 is directly connected to the output shaft 27, and while maintaining this state, the variator 2 is tilted in the direction in which the speed increasing side, that is, the power roller 10 approaches the power transmission shaft 7 on the output disk 9a, 9b side. When the rotation is made, the rotation speed of the counter shaft 14 is increased according to the tilt, and accordingly, the rotation speed of the sun gear 22 of the second planetary gear mechanism 3b is increased and the rotation speed of the output shaft 27 is increased. However, the speed ratio of the toroidal continuously variable transmission 1 as a whole increases.
[0041]
【The invention's effect】
As described above, according to the present invention, by using the half-toroidal continuously variable transmission, the spin loss at the contact surface is small and the power transmission efficiency can be improved. Further, the combination of the variator and the planetary gear mechanism provides an infinite transmission ratio. If the relative speed between the rotating sun gear and the carrier is “0”, the output rotational speed is “0”. By changing the relative speed, it is possible to start and reverse.
[Brief description of the drawings]
FIG. 1 is a system diagram of a half-toroidal continuously variable transmission according to a first embodiment of the present invention.
FIG. 2 is a system diagram of a half toroidal continuously variable transmission according to a second embodiment of the present invention.
FIG. 3 is a system diagram of a half-toroidal continuously variable transmission according to a third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 2 ... Variator 3 ... Planetary gear mechanism 4 ... Drive source 5 ... Input shaft 6 ... Hydraulic piston 8a, 8b ... Input disk 9a, 9b ... Output disk 10 ... Power roller 14 ... Counter shaft 27 ... Output shaft 28 ... Low speed clutch 29 ... High speed clutch

Claims (4)

An input shaft that is rotationally driven by a drive source, an output shaft that extracts power based on the rotation of the input shaft, a variator and a planetary gear mechanism disposed between the input shaft and the output shaft,
The variator includes a pair of opposed input disks that rotate in conjunction with the input shaft, a pair of output disks that are arranged coaxially between the pair of input disks and rotate in synchronization with each other, and the output disks. An output gear that rotates integrally with the power disk, a power transmission shaft that connects the pair of input disks, and a power roller that is in contact with the input disk and the output disk in a tiltable manner.
The planetary gear mechanism comprises a half toroid comprising a sun gear, a ring gear arranged around the sun gear, and a plurality of planetary gears rotatably supported by a carrier between the sun gear and the ring gear. in the form stepless transmission,
The input shaft, the power transmission shaft, the central axis of the planetary gear mechanism and the output shaft are on the same axis; and
Wherein a input and the hydraulic pressing mechanism for pressing in the axial direction towards the disk to the power rollers and the output disk, and a counter shaft for interlocking rotating the said output gear said sun gear, said counter rotation of the output disk A first power transmission mechanism including the counter shaft for transmitting the rotation of the sun gear of the planetary gear mechanism to a variator and transmitting the power to the sun gear of the planetary gear mechanism via a shaft; A half-toroidal continuously variable transmission comprising the second power transmission mechanism including the power transmission shaft and the central shaft for transmitting the rotation of the motor to the carrier of the planetary gear mechanism.   2. The half toroidal continuously variable transmission according to claim 1, wherein the hydraulic pressing mechanism is provided on the input shaft.   2. The half toroidal continuously variable transmission according to claim 1, wherein the hydraulic pressing mechanism is provided on the output disk side. 2. The half toroidal continuously variable transmission according to claim 1, wherein the planetary gear mechanism includes first and second planetary gear mechanisms.

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