WO2013175587A1

WO2013175587A1 - Power transmission device for vehicle

Info

Publication number: WO2013175587A1
Application number: PCT/JP2012/063179
Authority: WO
Inventors: 博文中田; 羽渕　良司
Original assignee: トヨタ自動車株式会社
Priority date: 2012-05-23
Filing date: 2012-05-23
Publication date: 2013-11-28
Also published as: JP5835477B2; JPWO2013175587A1

Abstract

A power transmission device for a vehicle, wherein a continuously variable transmission continuously changing the gear ratio and a gear train are arranged between an input shaft to which torque output by a drive force source is input and an output shaft that outputs the torque, so as to be capable of transmitting torque between the input shaft and the output shaft, said gear train having at least one gear ratio that cannot be set by the continuously variable transmission. The power transmission device for a vehicle has provided therein: a switching mechanism for changing to forward or backward drive, that performs differential action by using three rotational elements being an input element, an output element, and a reaction element that rotates the input element and the output element in mutually opposite directions by stopping rotation, said switching mechanism being arranged on the same axis line as the output shaft; a first clutch mechanism whereby the output element and the output shaft are coupled, and coupling at least two of the three rotational elements, and a brake mechanism that stops the rotation of the reaction element; a second clutch mechanism wherein the input shaft and the output element are coupled via the continuously variable transmission, and which transmits and disengages torque in a first torque transmission path extending from the input shaft, via the continuously variable transmission, to the output shaft; and a third clutch mechanism wherein the input shaft and the input element are coupled via the gear train and which transmits and disengages torque in a second torque transmission path from the input shaft to the input element via the gear train.

Description

Power transmission device for vehicle

The present invention relates to a device for transmitting power output from a driving force source of a vehicle, and in particular, includes a transmission path including a continuously variable transmission and another transmission path provided in parallel to the transmission path. The present invention relates to a power transmission device provided.

An internal combustion engine generally used as a driving force source of a vehicle has a characteristic that an output torque increases with an increase in the rotational speed. On the other hand, the driving force required for a vehicle is generally large at a low vehicle speed and relatively small at a high vehicle speed. That is, in the vehicle, a torque opposite to the torque based on the output characteristics of the internal combustion engine is required. In addition, the efficient operating points of the internal combustion engine are limited. Therefore, a vehicle that uses an internal combustion engine as a driving force source is equipped with a transmission that can change the gear ratio as appropriate. Then, by appropriately setting the gear ratio based on the vehicle running state such as the vehicle speed and the accelerator opening with the transmission, the required driving force is obtained and the internal combustion engine is operated at an efficient operating point. Yes. However, if there is a step in the gear ratio set by the transmission, such as a stepped transmission that sets the gear ratio step by step, the internal combustion engine is always operated at an efficient operating point. Can not. That is, when the rotational speed of the internal combustion engine at an efficient operating point is a rotational speed that can be set by the gear ratio between the two shift speeds, the period from when one shift speed is switched to the other shift speed. In the operating state, the efficiency is lowered. Therefore, recently, a continuously variable transmission capable of continuously changing a gear ratio has been used instead of a stepped transmission.

As a continuously variable transmission for a vehicle, a belt type continuously variable transmission and a toroidal type continuously variable transmission are widely known. The former belt-type continuously variable transmission has a power transmission belt and a pair of pulleys whose belt winding radius changes in size as the width of a groove around which the belt is wound is changed. Yes. The gear ratio set between the pair of pulleys is changed steplessly by changing the groove width of each pulley to change the winding radius of the belt. In the latter toroidal continuously variable transmission, the power roller is sandwiched between a pair of disks arranged opposite to each other, and the line connecting the contact points of the power roller with each disk is the axis of rotation center of the disk. Is different from each other in the number of rotations. Then, the larger the tilt angle (tilt angle) of the power roller, the greater the difference in rotational speed between the disks, that is, the gear ratio becomes farther away from “1”.

In these continuously variable transmissions, in order to continuously change the gear ratio, the torque is transmitted using the frictional force between the pulley and the belt or the frictional force between the disk and the power roller. . Since the frictional force is the product of the friction coefficient at the contact point of the two members and the vertical load (or load in the normal direction), the vertical load is increased according to the torque to be transmitted. In the belt type continuously variable transmission for a vehicle, the vertical load is a load with which the pulley pinches the belt. The load is generated by, for example, a hydraulic actuator integrally formed on the pulley and supplied to the hydraulic actuator.

On the other hand, a vehicle requires a large driving force when starting. On the other hand, the driving force required at the time of a steady driving state, that is, cruising is smaller than that at the time of starting. Therefore, it is necessary to increase the vertical load for generating the frictional force when starting. That is, in the belt type continuously variable transmission, the hydraulic pressure for generating the clamping pressure is increased at the time of start. If a hydraulic device that generates a large hydraulic pressure is provided in preparation for a start in a relatively short period of time as a driving state of the vehicle, the drive device and the hydraulic device for the same increase in size and generate a high hydraulic pressure. There is a possibility that fuel consumption will deteriorate.

Apparatuses aimed at solving such problems are described in Japanese Patent Application Laid-Open Nos. 2005-308041, 2004-077686, and 2000-130548. Among these, the device described in Japanese Patent Application Laid-Open No. 2005-308041 transmits the power output from the engine to the sun gear of the single pinion type planetary gear mechanism constituting the forward / reverse switching mechanism, and the sun gear is converted into a belt type. A clutch connected to an input shaft integrated with a primary pulley of the continuously variable transmission is provided. An input gear is fitted on the outer peripheral side of the input shaft via a one-way clutch, and this input gear is connected to a ring gear in the forward / reverse switching mechanism. The one-way clutch is configured to be engaged when the input shaft rotates at a higher speed than the input gear on the outer peripheral side in the forward rotation direction. An output gear is fitted on the outer peripheral side of the output shaft integral with the secondary pulley via another one-way clutch. An idle gear is disposed between the input gear and the output gear, and the input gear and the output gear mesh with the idle gear. That is, both the input gear and the output gear are configured to rotate in the same direction. The gear ratio (transmission ratio) between these input gears and output gears is slightly smaller than the largest transmission ratio that can be set by a continuously variable transmission comprising the above pulleys and the belt wound around them. Is set. The other one-way clutch is configured to be engaged when the output shaft rotates at a higher speed than the output gear in the forward rotation direction. In addition, a friction clutch is provided in parallel with the other one-way clutch. Further, a brake for fixing the carrier in the forward / reverse switching mechanism is provided to set the reverse state.

Therefore, in the device described in Japanese Patent Application Laid-Open No. 2005-308041, for example, when starting to travel forward, the sun gear and the input shaft are connected by the clutch, and the main transmission path mainly composed of a continuously variable transmission Torque is transmitted through the input shaft, and torque is transmitted when the one-way clutch is engaged with the sub-transmission path mainly composed of the gears. In that case, since the gear ratio by the gear train is somewhat smaller than the maximum gear ratio of the continuously variable transmission, the output gear rotates at a higher speed than the output shaft. As a result, the one-way clutch on the output shaft side is released, and torque is transmitted to the drive wheels through the gear train. That is, the continuously variable transmission is not subjected to a large torque at the start. Then, after the start, if the speed ratio of the continuously variable transmission is gradually reduced as the vehicle speed increases, the rotational speed of the output shaft integrated with the secondary pulley reaches the rotational speed of the output gear provided on the outer peripheral side, and the speed ratio The number of rotations further increases due to the decrease in. As a result, the one-way clutch on the output shaft side is engaged, and torque is transmitted to the drive wheels via the continuously variable transmission. In this case, since the one-way clutch on the input shaft side is in the released state, the interlock state does not occur. *

The device described in Japanese Patent Application Laid-Open No. 2004-077686 includes a single pinion type planetary gear mechanism between an input shaft for transmitting power output from an engine and a primary pulley in a belt type continuously variable transmission. A forward / reverse switching mechanism is provided. The ring gear and the primary pulley in the forward / reverse switching mechanism are connected to rotate integrally, and the input shaft is connected to the sun gear. Accordingly, the sun gear and the ring gear are connected by the clutch to move forward, and the carrier is fixed by the brake to move backward. Furthermore, a gear train having a gear ratio larger than the maximum gear ratio of the continuously variable transmission is provided between the input shaft and the output shaft integrated with the secondary pulley. An input gear constituting the gear train is integrated with the input shaft, and an output gear connected to the input shaft via an idle gear is rotatably fitted to the output shaft. A one-way clutch and a friction clutch are arranged in series between the output gear and the output shaft.

Therefore, when starting the vehicle in the forward state, the clutch for connecting the input shaft to the primary pulley is released, and the clutch on the output shaft side is engaged, so that the gear train and the one-way clutch from the input shaft and Torque is transmitted to the output shaft through a clutch arranged in series with this. If the input shaft and the primary pulley are connected by the clutch from that state, the maximum transmission ratio of the continuously variable transmission is somewhat smaller than the transmission ratio by the gear train, so the secondary pulley and the output shaft integrated with it are larger than before. The one-way clutch is disengaged at a higher rotational speed, more specifically, higher than the output gear. That is, torque is transmitted to the output shaft through the continuously variable transmission. As described above, since the gear train transmits torque at the time of starting, a large torque at the time of starting is not applied to the continuously variable transmission.

Japanese Patent Laid-Open No. 2000-130548 describes a transmission having the same configuration as the device described in Japanese Patent Laid-Open No. 2004-077686. That is, even in the transmission described in Japanese Patent Laid-Open No. 2000-130548, a one-way operation is performed between the output-side gear in the gear train that transmits torque when starting and the output shaft integrated with the secondary pulley. A clutch and a friction clutch are arranged in parallel.

In any of the devices described in these publications, a gear train is provided in parallel with the belt-type continuously variable transmission, and is configured to transmit torque for starting mainly through the gear train when starting. Yes. In the forward traveling state, the torque transmission path is switched in order to transmit the torque via the continuously variable transmission, and the switching is performed using a one-way clutch. However, in the one-way clutch, the torque transmission direction is limited to one direction, whereas when the vehicle actually travels, it is necessary to transmit the torque in either the forward or reverse direction. Further, depending on the configuration of the torque transmission path, it is necessary to prevent the one-way clutch from functioning. Therefore, it is necessary to use a one-way clutch and a friction clutch together as described in the above-mentioned publications. Therefore, in the configuration described in each of the above-mentioned publications, even if it is possible to avoid or suppress the large torque at the time of starting from acting on the continuously variable transmission, the overall configuration of the device becomes large and the on-vehicle performance is impaired. There is a possibility of becoming.

Further, both the device described in Japanese Patent Application Laid-Open No. 2005-308041 and the device described in Japanese Patent Application Laid-Open No. 2004-077686 include a forward / reverse switching mechanism including a planetary gear mechanism. In the configuration described in the former Japanese Patent Application Laid-Open No. 2005-308041, when traveling by transmitting torque by a belt type continuously variable transmission, torque from the engine is transmitted to the sun gear, and to the ring gear. Torque from the gear train is transmitted. Therefore, a large rotational speed difference occurs between the sun gear, the pinion gear, and the ring gear, which may cause power loss, deterioration of lubricating oil, noise, and vibration. In the latter configuration disclosed in Japanese Patent Application Laid-Open No. 2004-077686, when the gear train is traveling while transmitting torque, the sun gear of the planetary gear mechanism constituting the forward / reverse switching mechanism is connected to the sun gear of the planetary gear mechanism. The torque is transmitted to the ring gear from the output shaft side via the continuously variable transmission. As a result, similar to the device described in the above Japanese Patent Application Laid-Open No. 2005-308041, a large rotational speed difference occurs between the sun gear, the pinion gear, and the ring gear, which causes power loss, deterioration of lubricating oil, noise, May cause vibration.

The present invention has been made paying attention to the above technical problem, and is a vehicle power transmission device equipped with a continuously variable transmission, and has a maximum gear ratio or a minimum gear ratio that can be set by the continuously variable transmission. It is an object of the present invention to provide a vehicular power transmission device that can set a transmission ratio exceeding that, is easy to downsize, and has excellent durability.

In order to achieve the above object, the present invention provides a continuously variable transmission that continuously changes a gear ratio between an input shaft to which torque output from a driving force source is input and an output shaft that outputs torque. And a gear train having at least one speed ratio that cannot be set by the continuously variable transmission, respectively, in a vehicle power transmission device provided so that torque can be transmitted between the input shaft and the output shaft. A forward / reverse switching mechanism that performs a differential action by three rotating elements of an input element, an output element, and a reaction force element that rotates the input element and the output element in opposite directions when rotation is stopped, A first clutch machine that is disposed on the same axis as the output shaft, and that connects the output element and the output shaft, and connects at least any two rotating elements of the three rotating elements. And a brake mechanism for stopping the rotation of the reaction force element, the input shaft and the output element are connected via the continuously variable transmission, and from the input shaft via the continuously variable transmission A second clutch mechanism that transmits and shuts off torque is provided in the first torque transmission path that reaches the output shaft, and the input shaft and the input element are connected via the gear train, A third clutch mechanism for transmitting and interrupting torque is provided in a second torque transmission path from the input shaft to the input element via the gear train.

Further, the gear train according to the present invention is configured to set a speed ratio larger than a maximum speed ratio of the continuously variable transmission or a speed ratio smaller than a minimum speed ratio of the continuously variable transmission by a plurality of gears. be able to.

Further, the continuously variable transmission according to the present invention includes a drive-side member that transmits torque from the input shaft and an output-side member that outputs torque to the output shaft. The second clutch mechanism may be configured to be provided between the input shaft and the driving side member so as to selectively connect the input shaft and the driving side member.

Further, the continuously variable transmission according to the present invention includes a drive-side member that transmits torque from the input shaft and an output-side member that outputs torque to the output shaft. The second clutch mechanism may be provided between the output side member and the output shaft so as to selectively connect the output side member and the output shaft.

Also, the first clutch mechanism and the second clutch mechanism in the present invention can be constituted by friction clutches, respectively.

Further, the third clutch mechanism in the present invention can be constituted by a meshing clutch.

Further, the gear train according to the present invention includes a drive gear disposed on the same axis as the input shaft, an intermediate shaft, one idle gear provided on the intermediate shaft, or a plurality of gears that rotate integrally with each other. The idle gear, and a driven gear that transmits torque from the drive gear via the idle gear and is integrally connected to the input element. In that case, the third clutch mechanism according to the present invention can be configured to perform connection and disconnection between the input shaft and the drive gear.

Further, the gear train according to the present invention includes a drive gear disposed on the same axis as the input shaft, an intermediate shaft, one idle gear provided on the intermediate shaft, or a plurality of gears that rotate integrally with each other. The idle gear, and a driven gear that transmits torque from the drive gear via the idle gear and is integrally connected to the input element. In that case, the third clutch mechanism according to the present invention can be configured to perform connection and disconnection between the driven gear and the input element.

The gear train according to the present invention includes a drive gear arranged on the input shaft and connected to the input shaft, a driven gear integrally connected to the input element, an intermediate shaft, and the intermediate shaft A first idle gear provided above and meshing with the drive gear and a second idle gear meshing with the driven gear can be used. In that case, the third clutch mechanism according to the present invention can be configured to perform connection and disconnection between the first idle gear and the second idle gear.

The forward / reverse switching mechanism according to the present invention includes a sun gear that is an external gear, a ring gear that is an internal gear disposed concentrically with the sun gear, a first pinion gear that meshes with the sun gear, A double pinion type planetary gear mechanism including a first pinion gear and a second pinion gear meshing with the ring gear and a carrier holding the first pinion gear and the second pinion gear so as to rotate and revolve can be used.

Further, when the forward / reverse switching mechanism according to the present invention is constituted by the double pinion type planetary gear mechanism as described above, the sun gear is connected to the continuously variable transmission and the output shaft, and the carrier is the gear train. The ring gear can be configured to be stopped by the brake mechanism.

The forward / reverse switching mechanism according to the present invention includes a sun gear that is an external gear, a ring gear that is an internal gear disposed concentrically with the sun gear, a pinion gear that meshes with the sun gear and the ring gear, The pinion gear can be constituted by a single pinion type planetary gear mechanism provided with a carrier that holds the pinion gear so as to rotate and revolve.

In the present invention, when the forward / reverse switching mechanism is constituted by a single pinion type planetary gear mechanism as described above, the ring gear is connected to the continuously variable transmission and the output shaft, and the sun gear is The carrier may be connected to the gear train so that the carrier is stopped from rotating by the brake mechanism.

In the forward / reverse switching mechanism according to the present invention, the plurality of rotating elements are indicated by straight lines parallel to each other, and the lengths from the intersections with the base lines orthogonal to the straight lines and the positions of the rotating elements at the positions with respect to the base lines It can be configured by a planetary gear mechanism that can represent the respective rotation speeds of the input element, the output element, and the reaction force element by a collinear chart showing the speed. In that case, the reaction force element is an element represented by a line located in the center of the collinear diagram, and the input element is an element represented by one of the left and right lines in the collinear diagram. Furthermore, the output element may be an element represented by one of the left and right lines in the alignment chart.

Therefore, according to the present invention, by connecting at least two rotating elements in the forward / reverse switching mechanism by the first clutch mechanism, the entire forward / reverse switching mechanism rotates integrally, and the forward / reverse switching mechanism and the output shaft And can transmit power. In this state, by releasing the second clutch mechanism and engaging the third clutch mechanism, the continuously variable transmission is disconnected from the output shaft, and the gear train is connected to the output shaft via the forward / reverse switching mechanism. Connected. That is, the input shaft and the output shaft are connected via the gear train and the forward / reverse switching mechanism. The gear ratio by the gear train is a gear ratio that cannot be set by the continuously variable transmission, and is a gear ratio that is larger than the maximum gear ratio in the continuously variable transmission or smaller than the minimum gear ratio. Therefore, the transmission gear ratio as a whole of the power transmission device can be made wider than the transmission gear ratio that can be set by the continuously variable transmission.

If the brake mechanism is engaged instead of the first clutch mechanism, the reaction element of the forward / reverse switching mechanism is stopped from rotating and the output element rotates in the opposite direction with respect to the input element. That is, the vehicle can travel backward. In that case, torque is transmitted from the output element to the output shaft via the third clutch mechanism and the gear train. Therefore, the gear ratio set as a whole of the power transmission device in that case is a large gear ratio that cannot be set by the continuously variable transmission.

Torque is input from the output shaft when the vehicle is decelerating, but a second clutch mechanism is provided between the driven member of the continuously variable transmission and the output shaft to release the second clutch mechanism. Thus, the torque input to the continuously variable transmission from the output shaft can be cut off to protect the continuously variable transmission.

Further, when the continuously variable transmission is controlled so that the gear ratio thereof is close to the gear ratio in the gear train, the second clutch mechanism is engaged and the first clutch mechanism is released, so that the input shaft and the output The shaft is connected via a second clutch mechanism and a continuously variable transmission. The gear train is cut off with respect to the input shaft. Therefore, the transmission gear ratio can be appropriately set by the continuously variable transmission. In this case, if the first clutch mechanism and the second clutch mechanism are constituted by a friction clutch capable of gradually changing the transmission torque capacity, the amount of torque handled by the first clutch mechanism and the second clutch mechanism is gradually changed. Thereby, the change of the torque of an output shaft can be made smooth. As a result, a sense of incongruity caused by a shift shock or a change in driving force can be prevented or suppressed.

If the third clutch mechanism is released while the second clutch mechanism is engaged and the first clutch mechanism is released as described above, the gear train is also disconnected from the output shaft. Therefore, when traveling with torque transmitted by a continuously variable transmission, the gear train is rotated, or torque is input not only from the input element of the forward / reverse switching mechanism but also from the output element, and the difference in rotational speed between the elements. Can be avoided. As a result, power loss can be reduced, durability can be improved, and noise and vibration can be suppressed. And by making the 3rd clutch mechanism into a meshing clutch, the structure as a whole of a power transmission device can be simplified and reduced in size. Further, since the third clutch mechanism is engaged or released in a state where almost no torque is applied, the engagement and release operations are not hindered.

According to the invention, the forward / reverse switching mechanism is disposed on the same axis as the output shaft, and the output element is connected to the output shaft, so that the forward / reverse switching mechanism is other than the output shaft. The inertial mass of the output shaft is larger than when arranged on the shaft. If the inertial mass on the output shaft side is small, the output shaft is likely to vibrate, and so-called booming noise may occur when traveling at a low speed by transmitting torque by the continuously variable transmission. In contrast, as described above, the forward / reverse switching mechanism is placed on the same axis as the output shaft, and the inertial mass of the output shaft is increased, thereby suppressing the generation of humming noise during low-speed traveling by a continuously variable transmission. can do.

According to the present invention, the first clutch mechanism, the second clutch mechanism, the third clutch mechanism, and the brake mechanism can be configured by a single mechanism such as a friction type or meshing type clutch or brake. it can. Therefore, the configuration of the entire power transmission device can be simplified and downsized. Further, by configuring the forward / reverse switching mechanism with a single-pinion type or double-pinion type planetary gear mechanism, the axial length of the entire power transmission device can be shortened, and the on-vehicle performance can be improved.

It is a skeleton figure for demonstrating an example of the power transmission device for vehicles which concerns on this invention. FIG. 5 is a collinear chart (speed diagram) collectively showing the rotation states of the rotating elements when the forward / reverse switching mechanism is constituted by a double pinion type planetary gear mechanism. It is a table | surface which shows the operation state of each clutch mechanism and a brake mechanism collectively. It is a skeleton figure for demonstrating the 2nd example of this invention. It is a skeleton figure for demonstrating the 3rd example of this invention. It is a skeleton figure for demonstrating the 4th example of this invention. It is a skeleton figure for demonstrating the 5th example of this invention. It is a skeleton figure for demonstrating the 6th example of this invention. It is a skeleton figure which shows the example of the forward / reverse switching mechanism which consists of a single pinion type planetary gear mechanism. FIG. 6 is a collinear chart (speed diagram) showing the rotational states of the rotating elements together when the forward / reverse switching mechanism is a single pinion type planetary gear mechanism.

Next, the present invention will be described with reference to specific examples. A power transmission device according to the present invention is a device for transmitting power output from a driving force source such as an engine or a motor to driving wheels and has a speed change function. That is, it is a device generally called a transmission or a transaxle. In particular, the device targeted in the present invention is a power transmission device having a continuously variable transmission and a gear train having a predetermined gear ratio (gear ratio) arranged in parallel with each other between an input shaft and an output shaft. . The continuously variable transmission may be a conventionally known belt-type continuously variable transmission or toroidal continuously variable transmission. The belt type continuously variable transmission is suitable for a power transmission device mounted on an FF vehicle (front engine / front drive vehicle). The toroidal continuously variable transmission is suitable for a power transmission device mounted on an FR vehicle (front engine / rear drive vehicle). The gear train may be any gear that can transmit torque from the input shaft to the output shaft. However, in the present invention, a gear ratio that cannot be set by the continuously variable transmission is set by the gear train. . Therefore, the gear train is configured by meshing a plurality of gears. And the gear ratio (ratio of the number of teeth) can be set so that a gear ratio larger than the maximum gear ratio in the continuously variable transmission or smaller than the minimum gear ratio can be set. In order to prevent a large torque from being applied to the continuously variable transmission when the vehicle starts, the gear train may be configured so that a gear ratio larger than the maximum gear ratio of the continuously variable transmission can be set. preferable. In order to reduce the rotational speed of the driving force source during traveling and to reduce fuel consumption, it is preferable that the gear train be configured so that a gear ratio smaller than the minimum gear ratio in the continuously variable transmission can be set.

A specific example of such a power transmission device is shown in FIG. The example shown here is an example configured to be suitable for an FF vehicle, and therefore, a belt-type continuously variable transmission is adopted as the continuously variable transmission 1. The driving force source is constituted by an internal combustion engine (E / G; engine) 2 such as a gasoline engine or a diesel engine.

The torque converter 3 with a lock-up clutch is connected to the output shaft (crankshaft) of the engine 2. The torque converter 3 has a configuration that has been widely known in the past. Specifically, a turbine runner 6 is disposed so as to face a pump impeller 5 integrated with the front cover 4. A stator 7 is disposed between the pump impeller 5 and the turbine runner 6 through a one-way clutch (not shown). A lockup clutch 8 that rotates integrally with the turbine runner 6 is disposed to face the inner surface of the front cover 4. The lockup clutch 8 is engaged / released according to the pressure difference between both sides of the lockup clutch 8. That is, the lock-up clutch 8 is brought into an engaged state in which the torque is transmitted by contacting the inner surface of the front cover 4, and on the contrary, a released state in which the torque transmission is interrupted away from the inner surface of the front cover 4. It is configured. An input shaft 9 is connected to the turbine runner 6.

As is conventionally known, the continuously variable transmission 1 includes a primary pulley 10 that is a driving member, a secondary pulley 11 that is a driven member, and a belt 12 that is wound around the primary pulley 10 and the secondary pulley 11. And. The primary pulley 10 and the secondary pulley 11 are configured such that the winding radius of the belt 12 is changed to be larger or smaller by changing the width of the groove around which the belt 12 is wound. . That is, the gear ratio is continuously changed by changing the groove widths of the primary pulley 10 and the secondary pulley 11 around which the belt 12 is wound.

The primary pulley 10 is disposed on the same axis as the input shaft 9 and on the opposite side of the engine 2 with the torque converter 3 interposed therebetween. That is, the primary shaft 13 integrated with the primary pulley 10 is connected to the input shaft 9 via the second clutch mechanism C2 described later. Further, the secondary pulley 11 is arranged so that the rotation center axis thereof is parallel to the rotation center axis of the primary pulley 10. The secondary pulley 11 includes a secondary shaft 14 provided along the rotation center axis. An output shaft 15 is disposed on the same axis as the secondary shaft 14, and the secondary shaft 14 and the output shaft 15 are integrally connected. Therefore, the output shaft 15 is parallel to the input shaft 9 described above.

A third clutch mechanism C3 and a second clutch mechanism C2 are provided between the input shaft 9 and the primary shaft 13 described above. That is, the third clutch mechanism C3 and the second clutch mechanism C2 are arranged on the input shaft 9 from the side close to the engine 2 and the torque converter 3. The third clutch mechanism C3 is a mechanism for selectively connecting the input shaft 9 and a drive gear 25 of a gear train 23 described later. The second clutch mechanism C2 is a mechanism for selectively connecting the input shaft 9 and the primary shaft 13. The second clutch mechanism C2 only needs to be capable of selectively transmitting and interrupting torque between the input shaft 9 and the primary shaft 13. For example, it may be either a friction clutch or a meshing clutch, but it is preferably constituted by a wet or dry friction clutch in which the transmission torque capacity gradually increases or decreases according to the engagement force.

In the power transmission device according to the present invention, the forward / reverse switching mechanism 16 is disposed on the same axis as the output shaft 15 connected to the secondary shaft 14 of the continuously variable transmission 1. The forward / reverse switching mechanism 16 has a forward state in which the torque transmitted from the input shaft 9 is transmitted without changing its direction, and a reverse state in which the torque transmitted from the input shaft 9 is transmitted in a reverse direction. It is a mechanism for switching. In the present invention, the forward / reverse switching mechanism 16 is constituted by a so-called differential mechanism in which the three rotating elements make a differential action with each other. Various differential mechanisms of this type have been known in the past, and any differential mechanism can be employed in the present invention. In the example shown in FIG. 1, the forward / reverse switching mechanism 16 is constituted by a double pinion type planetary gear mechanism.

The double pinion type planetary gear mechanism includes a sun gear 17 that is an external gear, a ring gear 18 that is an internal gear disposed concentrically with the sun gear 17, a first pinion gear 19 that meshes with the sun gear 17, A second pinion gear 20 meshed with the first pinion gear 19 and the ring gear 18 and a carrier 21 holding the first pinion gear 19 and the second pinion gear 20 so as to be capable of rotating and revolving are provided. The input shaft 9 is connected to the carrier 21 via a gear train 23 described later. Therefore, the carrier 21 is an input element. A brake mechanism B that selectively stops the rotation of the ring gear 18 is provided. Therefore, the ring gear 18 is a reaction force element. The brake mechanism B is provided between the ring gear 18 and a fixed portion 22 such as a casing, and can be constituted by a friction brake such as a multi-plate brake or a meshing brake.

Further, the secondary shaft 14 and the output shaft 15 of the continuously variable transmission 1 are integrally connected to the sun gear 17. Therefore, the sun gear 17 is an output element. Between the sun gear 17 and the carrier 21, there is provided a first clutch mechanism C1 for connecting the sun gear 17 and the carrier 21 so as to integrally rotate the entire planetary gear mechanism. The first clutch mechanism C1 is a clutch that can be referred to as a forward clutch, and is for setting a forward traveling state. The first clutch mechanism C1 may be any mechanism that can selectively transmit and shut off torque. For example, it may be either a friction clutch or a meshing clutch, but it is preferably constituted by a wet or dry friction clutch in which the transmission torque capacity gradually increases or decreases according to the engagement force. The first clutch mechanism C1 is preferably configured to directly transmit the torque of the input shaft 9 to the carrier 21 that is an input element.

In short, the first clutch mechanism C1 connects the at least two rotating elements of the three rotating elements in the planetary gear mechanism constituting the forward / reverse switching mechanism 16 so as to integrate the entire planetary gear mechanism. It suffices to be configured. In addition to the configuration in which the sun gear 17 and the carrier 21 are coupled as in the example shown in FIG. 1, for example, the “forward clutch” described in Japanese Patent Application Laid-Open Nos. 2010-276159 and 2010-216613 is used. In this way, the sun gear and the ring gear can be connected. Alternatively, as in the “forward clutch” described in JP-A-2005-337360, the carrier and the ring gear can be connected. Further, all the three rotating elements may be connected to each other so that the entire planetary gear mechanism is integrated.

The planetary gear mechanism constituting the forward / reverse switching mechanism 16 can be represented by a collinear diagram (speed diagram). An example of an alignment chart representing the forward / reverse switching mechanism 16 shown in FIG. 1 is shown in FIG. In FIG. 2, the sun gear 17, the ring gear 18, and the carrier 21 are represented by straight lines parallel to each other. Among these straight lines, a straight line indicating the sun gear 17 and a straight line indicating the carrier 21 are located at both left and right ends, and a straight line indicating the ring gear 18 which is a reaction force element is arranged at the center thereof. When the distance between the straight line indicating the sun gear 17 and the straight line indicating the carrier 21 is “1”, the distance between the straight line indicating the sun gear 17 and the straight line indicating the ring gear 18 is the number of teeth of the carrier 21 and the teeth of the ring gear 18. It is set to a value corresponding to the ratio to the number (that is, gear ratio). The distance from the intersection of each straight line with the base line L0 indicates the number of rotations of each rotating element. The position with respect to the base line L0 indicates the rotation direction of each rotation element. Therefore, when the first clutch mechanism C1 is engaged, the entire forward / reverse switching mechanism 16 rotates as a whole, so that the rotational speed of each rotating element is indicated by a straight line Lf. On the other hand, when the ring gear 18 is fixed by the brake mechanism B, the rotation speed and the rotation direction of each rotating element are indicated by a straight line Lr. That is, the sun gear 17 rotates in the opposite direction with respect to the carrier 21.

In the power transmission device according to the present invention, a gear train 23 composed of a plurality of parallel gears is provided in parallel with the continuously variable transmission 1. The gear train 23 is configured as a speed reduction mechanism that sets a speed ratio larger than the maximum speed ratio in the continuously variable transmission 1 or a speed increase mechanism that sets a speed ratio smaller than the minimum speed ratio in the continuously variable transmission 1. Has been. In the example shown in FIG. 1, the gear train 23 is configured as a speed reduction mechanism when torque is transmitted from the input shaft 9 toward the output shaft 15. Then, a drive gear arranged on the same axis as the input shaft 9, an idle gear for making the rotation directions of the input shaft 9 and the output shaft 15 the same, and torque from the drive gear via the idle gear Is provided with a driven gear.

Specifically, a counter shaft 24 corresponding to the intermediate shaft in the present invention is arranged in parallel to the input shaft 9 and the output shaft 15. A drive gear 25 is disposed on the input shaft 9 so as to be able to rotate relative to the input shaft 9. A counter driven gear 26 meshing with the drive gear 25 is attached to and integrated with the counter shaft 24. A counter drive gear 27 having a larger diameter than the counter driven gear 26 is attached to and integrated with the counter shaft 24. A driven gear 28 meshed with the counter drive gear 27 is integrally connected to a carrier 21 that is an input element in the forward / reverse switching mechanism 16. Therefore, the counter driven gear 26 and the counter drive gear 27 described above correspond to the idle gear in the present invention.

The driven gear 28 has a larger diameter than that of the counter drive gear 27, and is configured to cause a deceleration action when torque is transmitted from the counter drive gear 27 toward the driven gear 28. Therefore, the speed ratio (gear ratio) of the gear train 23 is obtained by multiplying the speed ratio between the drive gear 25 and the counter driven gear 26 and the speed ratio between the counter drive gear 27 and the driven gear 28. It becomes. The gear train 23 shown in FIG. 1 is configured such that the value of the gear ratio is larger than the maximum gear ratio in the continuously variable transmission 1.

In the example shown in FIG. 1, the drive gear 25 is connected to the input shaft 9, and a third clutch mechanism C3 for releasing the connection is provided. Therefore, the first clutch mechanism C1 is provided on the output shaft 15 side of the gear train 23, and the third clutch mechanism C3 is provided on the input shaft 9 side of the gear train 23. Here, since the first clutch mechanism C1 may be a friction clutch, the third clutch mechanism C3 may be configured to switch between two states of engagement and disengagement. That is, the third clutch mechanism C3 does not need to take a value between 0 and the maximum value of the transmission torque capacity. Therefore, the third clutch mechanism C3 can be configured by a meshing clutch such as a dog clutch or a synchronizer. FIG. 1 shows an example in which the third clutch mechanism C3 is configured by a synchronizer. In other words, the third clutch mechanism C3 fits the drive gear 25 to the input shaft 9 by fitting the sleeve 29 to the spline formed on the boss portion of the drive gear 25 and the spline formed on the hub of the input shaft 9. It is comprised so that it may connect.

The example shown in FIG. 1 is an example configured to be suitable for an FF vehicle as described above. Accordingly, the torque is output from the output shaft 15 to the front differential 30 which is a final reduction gear. That is, an output gear 31 is attached to the output shaft 15, and a large-diameter gear 32 that meshes with the output gear 31 is attached to the reduction gear shaft 33. A small diameter gear 34 is attached to the reduction gear shaft 33, and the small diameter gear 34 meshes with the ring gear 35 of the front differential 30. The front differential 30 is configured to transmit torque transmitted through the ring gear 35 from the left and right drive shafts 36 to drive wheels (not shown).

The power transmission device according to the present invention transmits torque from the input shaft 9 to the output shaft 15 via the torque transmission path provided with the gear train 23 when starting in the forward direction and traveling backward. When traveling forward with the vehicle speed increased to some extent, control is performed so that torque is transmitted from the input shaft 9 to the output shaft 15 via a torque transmission path provided with the continuously variable transmission 1. For example, when a drive position (drive range) is selected by a shift device (not shown), the first clutch mechanism C1 and the third clutch mechanism C3 are engaged, and the second clutch mechanism C2 and the brake mechanism B are released. Be made. FIG. 3 shows a table showing such engagement and disengagement states. In FIG. 3, “ON” indicates engagement, and “OFF” indicates release. Further, “ON” in parentheses indicates that the engagement state is transitively.

By setting the clutch mechanisms C1, C2, C3 and the brake mechanism B as shown in the table shown in FIG. 3 when starting in the forward direction, the torque output from the engine 2 is changed to the input shaft 9, the third clutch. It is transmitted to the output shaft 15 via C3, the gear train 23, and the forward / reverse switching mechanism 16. That is, since the drive gear 25 in the gear train 23 is connected to the input shaft 9 by the third clutch mechanism C3, the torque of the input shaft 9 is transferred from the driven gear 28 to the carrier of the forward / reverse switching mechanism 15 via the gear train 23. 21 is transmitted. At the same time, it is transmitted to the sun gear 17 via the first clutch mechanism C1. At the time of forward movement, the forward / reverse switching mechanism 16 is integrated with the entire forward / reverse switching mechanism 16 because the two rotating elements of the sun gear 17 and the carrier 21 are connected by the first clutch mechanism C1. Therefore, the forward / reverse switching mechanism 16 transmits the torque input from the carrier 21 as it is from the sun gear 17 to the output shaft 15 without causing an acceleration / deceleration action.

Then, the torque transmitted to the output shaft 15 is transmitted from the output gear 31 to the left and right drive wheels via the reduction gear train and the front differential 30, and the vehicle starts. The continuously variable transmission 1 is always connected to the output shaft 15 or the sun gear 17. Therefore, the torque input to the forward / reverse switching mechanism 16 is also transmitted to the secondary pulley 11 of the continuously variable transmission 1. However, at the time of start, the second clutch mechanism C2 is in a released state, and is separated so that torque is not transmitted between the continuously variable transmission 1 and the input shaft 9. Therefore, no torque is transmitted between the input shaft 9 and the output shaft 15 via the continuously variable transmission 1, and a so-called interlock state is not obtained.

Thus, when starting, torque is transmitted from the input shaft 9 to the output shaft 15 via the gear train 23. As the gear train 23 functions as a speed reduction mechanism, the gear ratio between the input shaft 9 and the output shaft 15 is larger than the maximum gear ratio that can be set by the continuously variable transmission 1. As a result, a large driving force can be obtained for the vehicle. Further, since a large torque is not applied to the continuously variable transmission 1 at the time of starting, it is not necessary to increase the hydraulic pressure for setting the transmission torque capacity. Therefore, consumption of power for generating high-pressure hydraulic pressure can be reduced, fuel efficiency can be improved, and durability of the continuously variable transmission 1 can be improved.

When the vehicle speed is increased to a predetermined vehicle speed after starting, the first clutch mechanism C1 is released with the gear ratio of the continuously variable transmission 1 set to a maximum value or a gear ratio close thereto. . At the same time, the second clutch mechanism C2 is engaged. The forward / reverse switching mechanism 16 is in a state of so-called free rotation because the first clutch mechanism C1 is further released while the brake mechanism B is released. As a result, the connection between the output shaft 15 and the gear train 23 is released. On the other hand, the primary pulley 10 is connected to the input shaft 9 by the second clutch mechanism C2. Therefore, the input shaft 9 and the output shaft 15 are coupled so as to transmit torque via the continuously variable transmission 1. Therefore, the engine speed can be set to a speed with good fuel consumption by gradually decreasing the speed ratio of the continuously variable transmission 1 or changing the speed ratio according to the vehicle speed and the accelerator opening.

When switching from the torque transmission state via the gear train 23 to the torque transmission state via the continuously variable transmission 1 as described above, the gear ratio by the gear train 23 is greater than the maximum gear ratio of the continuously variable transmission 1. Since it is large, the gear ratio or the driving force changes. Therefore, when the first clutch mechanism C1 is released and the second clutch mechanism C2 is engaged, the first clutch mechanism C1 and the second clutch mechanism C2 are controlled to slip and engage. That is, by gradually increasing the engagement pressure of the second clutch mechanism C2, the transmission torque capacity is gradually increased. At the same time, the transmission torque capacity is gradually reduced by gradually reducing the engagement pressure of the first clutch mechanism C1. This control is conventionally known as clutch-to-clutch control. By controlling the first clutch mechanism C1 and the second clutch mechanism C2 in this manner, it is possible to avoid or suppress the torque of the output shaft 15 from changing smoothly and causing a shift shock or a sense of discomfort.

After the first clutch mechanism C1 is disengaged and the second clutch mechanism C2 is completely engaged and torque transmission via the continuously variable transmission 1 is stably performed, the third clutch mechanism C3 is released. That is, the gear train 23 is also disconnected from the input shaft 9. As a result, torque from the secondary pulley 11 is transmitted to the sun gear 17 in the forward / reverse switching mechanism 16. However, since the ring gear 18 and the carrier 21 can freely rotate, a rotational speed difference is generated between the rotating elements constituting the forward / reverse switching mechanism 16. However, it is possible to suppress power loss and durability reduction, or noise or vibration in the forward / reverse switching mechanism 16. Note that when the third clutch mechanism C3 is released, the first clutch mechanism C1 has already been released, and thus no torque is applied to the gear train 23. Therefore, even if the third clutch mechanism C3 is constituted by a meshing clutch, the third clutch mechanism C3 can be released during traveling. In other words, by configuring the power transmission device according to the present invention as described above, the third clutch mechanism C3 can be configured by a meshing clutch.

On the other hand, when traveling backward, as shown in FIG. 3, the first clutch mechanism C1 and the second clutch mechanism C2 are released and the third clutch mechanism C3 and the brake mechanism B are engaged. In this case, in the forward / reverse switching mechanism 16, torque from the engine 2 is input to the carrier 21 via the gear train 23 while the ring gear 18 is fixed by the brake mechanism B. Therefore, the sun gear 17 rotates in the opposite direction with respect to the carrier 21. Accordingly, torque is transmitted from the input shaft 9 to the output shaft 15 via the gear train 23 as in the case of starting during forward traveling. In this case, the output shaft 15 rotates in the reverse traveling direction. Further, the gear ratio in this case is a gear ratio obtained by multiplying the gear ratio by the gear train 23 and the gear ratio by the planetary gear mechanism constituting the forward / reverse switching mechanism 16. Then, torque is transmitted from the output gear 31 to the left and right drive wheels via the reduction gear train and the front differential 30, and the vehicle travels backward. The second clutch mechanism C2 is disengaged and is separated so that torque transmission does not occur between the continuously variable transmission 1 and the input shaft 9. Therefore, no torque is transmitted between the input shaft 9 and the output shaft 15 via the continuously variable transmission 1, and a so-called interlock state is not obtained.

As described above, according to the power transmission device of the present invention, when starting in the forward direction or when traveling backward, a large gear ratio that cannot be set by the continuously variable transmission 1 can be set. Therefore, start acceleration can be improved, and power performance during reverse travel can be improved. Further, in these cases, the continuously variable transmission 1 is not involved in the transmission of torque for traveling, so there is no need to increase the belt clamping pressure in the continuously variable transmission 1. Therefore, power consumption can be reduced by reducing the consumption of power for generating the clamping pressure. Further, the durability of the continuously variable transmission 1 can be improved. Furthermore, in the power transmission device according to the present invention, each clutch mechanism can have a single configuration such as a friction clutch or a meshing clutch. Therefore, it is possible to simplify the overall configuration of the power transmission device by reducing the number of necessary components. Further, the power transmission device can be reduced in size.

Further, in the power transmission device having the configuration shown in FIG. 1 described above, the second clutch mechanism C2 is provided on the input shaft 9. Therefore, the torque applied to the second clutch mechanism C2 from the input shaft 9 side during forward traveling is a torque that is not subjected to the speed increasing / decreasing action except for the torque converter 3. In other words, in the driving state, torque that is equal to or higher than the torque at the input shaft 9 is not applied to the second clutch mechanism C2. Therefore, the torque capacity of the second clutch mechanism C2 is smaller than that in the case where the second clutch mechanism C2 is provided on the output shaft 15 or the counter shaft 24 where a large torque may be applied to the second clutch mechanism C2. It can be a small clutch.

Similarly, in the power transmission device having the configuration shown in FIG. 1, the third clutch mechanism C <b> 3 is provided on the input shaft 9 between the input shaft 9 and the drive gear 25 of the gear train 23. When the third clutch mechanism C3 transmits torque to the output shaft 15 side via the gear train 23, the gear train 23 functions as a speed reduction mechanism on the output side of the third clutch mechanism C3. Therefore, the torque increased by the gear train 23 is not applied to the third clutch mechanism C3. Therefore, the torque capacity of the third clutch mechanism C3 is small compared to the case where the third clutch mechanism C3 is provided on the output shaft 15 or the counter shaft 24 where a large torque may be applied to the third clutch mechanism C3. It can be a small clutch.

In the power transmission device according to the present invention, when torque is transmitted from the input shaft 9 to the output shaft 15 via the torque transmission path including the gear train 23, the torque transmission path including the continuously variable transmission 1 is the input shaft. 9 or the output shaft 15. On the other hand, when torque is transmitted between the input shaft 9 and the output shaft 15 via the torque transmission path provided with the continuously variable transmission 1, the torque transmission path provided with the gear train 23 is used as the input shaft 9. Alternatively, it is disconnected from the output shaft 15. Therefore, the second clutch mechanism C2 and the third clutch mechanism C3 are not necessarily provided at the positions shown in FIG. Therefore, the second clutch mechanism C2 and the third clutch mechanism C3 can be provided at appropriate positions within a range that does not impair their original functions. Hereinafter, other configuration examples will be described with reference to FIGS.

In the power transmission device shown in FIG. 4, the third clutch mechanism C3 of the configuration shown in FIG. 1 is arranged on the same axis as the output shaft 15 together with the forward / reverse switching mechanism 16, and the others are the same as in the example shown in FIG. It is configured. Therefore, only the parts different from FIG. 1 in the configuration of FIG. 4 will be described, and the same reference numerals as those in FIG.

The third clutch mechanism C3 is a meshing clutch as described above, and is disposed on the same axis as the output shaft 15 or the secondary shaft 14 in the example shown in FIG. The third clutch mechanism C3 in the example shown in FIG. 4 selectively transmits and blocks torque between the driven gear 28 of the gear train 23 and the carrier 21 that is an input element in the forward / reverse switching mechanism 16. Configured to do. With the arrangement of the third clutch mechanism C3 changed as described above with respect to the configuration shown in FIG. ing. Further, the input shaft 9 and the primary shaft 13 of the continuously variable transmission 1 are connected only through the second clutch mechanism C2.

Also in the power transmission device configured as shown in FIG. 4, the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the brake mechanism B are used when starting in the forward direction and during forward travel. And during reverse travel, they are engaged or released as shown in FIG. As in the case of the power transmission device shown in FIG. 1 described above, torque transmission via the torque transmission path mainly composed of the gear train 23 and the torque transmission path mainly composed of the continuously variable transmission 1 are performed. Torque transmission is performed. And it is made to act similarly to the power transmission device shown in FIG. 1, and the same effect can be acquired.

In the configuration shown in FIG. 4, the second clutch mechanism C2 is arranged on the so-called input side of the continuously variable transmission 1, similarly to the configuration of the power transmission device shown in FIG. Therefore, as in the case of the power transmission device shown in FIG. 1 described above, when traveling forward with the power of the engine 2, a torque greater than the torque transmitted from the engine 2 to the input shaft 9 is applied to the second clutch mechanism. It doesn't run on C2. Therefore, also in the configuration shown in FIG. 4, the second clutch mechanism C2 can be downsized.

4, the third clutch mechanism C3 is disposed on the same axis as the output shaft 15 as described above. Therefore, the torque transmitted from the engine 2 to the input shaft 9 is decelerated by the gear train 23 and transmitted to the rotating member on the driven gear 28 side in the third clutch mechanism C3. As a result, compared with the case where the torque from the engine 2 is transmitted to the third clutch mechanism C3 at the same rotational speed, the rotating member on the driven gear 28 side and the rotating member on the carrier 21 side in the third clutch mechanism C3 The rotational speed difference between the two becomes smaller. In other words, the rotational speed difference between the input side rotating member and the output side rotating member in the third clutch mechanism C3 is reduced. Therefore, engagement control in the third clutch mechanism C3 can be easily performed. Further, the durability of the third clutch mechanism C3 can be improved.

In the power transmission device shown in FIG. 5, the third clutch mechanism C3 in the configuration shown in FIG. 1 is arranged on the same axis as the counter shaft 24 of the gear train 23 corresponding to the intermediate shaft in the present invention. The configuration is the same as the example shown in FIG. Therefore, only the parts different from FIG. 1 in the configuration of FIG. 5 will be described, and the same reference numerals as those in FIG.

The third clutch mechanism C3 is a meshing clutch as described above, and is arranged on the same axis as the countershaft 24 in the gear train 23 in the example shown in FIG. The third clutch mechanism C3 in the example shown in FIG. 5 selectively performs torque transmission and interruption between the counter shaft 24 and the counter drive gear 27 that is one of the idle gears in the gear train 23. It is configured as follows. With the arrangement of the third clutch mechanism C3 changed as described above with respect to the configuration shown in FIG. ing. Further, the input shaft 9 and the primary shaft 13 of the continuously variable transmission 1 are connected only through the second clutch mechanism C2.

Also in the power transmission device configured as shown in FIG. 5, the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the brake mechanism B are used for starting in the forward direction and for traveling forward. And during reverse travel, they are engaged or released as shown in FIG. As in the case of the power transmission device shown in FIG. 1 described above, torque transmission via the torque transmission path mainly composed of the gear train 23 and the torque transmission path mainly composed of the continuously variable transmission 1 are performed. Torque transmission is performed. And it is made to act similarly to the power transmission device shown in FIG. 1, and the same effect can be acquired.

In the configuration shown in FIG. 5, the second clutch mechanism C2 is arranged on the so-called input side of the continuously variable transmission 1, similarly to the configuration of the power transmission device shown in FIG. Therefore, as in the case of the power transmission device shown in FIG. 1 described above, when traveling forward with the power of the engine 2, a torque greater than the torque transmitted from the engine 2 to the input shaft 9 is applied to the second clutch mechanism. It doesn't run on C2. Therefore, also in the configuration shown in FIG. 5, the second clutch mechanism C2 can be downsized.

In the configuration shown in FIG. 5, the third clutch mechanism C3 is arranged on the same axis as the counter shaft 24 of the gear train 23 as described above. Therefore, the gear pair of the drive gear 25 and the counter driven gear 26 in the gear train 23 is configured as a speed reduction mechanism in the case of transmitting torque from the input shaft 9 to the counter shaft 24, so that the engine 2 can be connected to the input shaft 9. The transmitted torque is decelerated between the drive gear 25 and the counter driven gear 26 in the gear train 23 and is transmitted to the rotating member on the counter shaft 24 side in the third clutch mechanism C3. As a result, compared to the case where the torque from the engine 2 is transmitted to the third clutch mechanism C3 at the same rotation speed, the driven gear 28 side, that is, the input side rotating member and the carrier 21 side in the third clutch mechanism C3, that is, The rotational speed difference with the output side rotating member is reduced. Therefore, engagement control in the third clutch mechanism C3 can be easily performed. Further, the durability of the third clutch mechanism C3 can be improved.

In the power transmission device shown in FIG. 6, the second clutch mechanism C2 of the configuration shown in FIG. 1 is arranged on the same axis as the output shaft 15 together with the forward / reverse switching mechanism 16, and the rest is the same as the example shown in FIG. It is configured. Therefore, only the parts different from FIG. 1 in the configuration of FIG. 6 will be described, and the same reference numerals as those in FIG.

The second clutch mechanism C2 in the present invention is a clutch that transmits and interrupts torque through a torque transmission path from the input shaft 9 to the output shaft 15 via the continuously variable transmission 1. In the example shown in FIG. 6, the second clutch mechanism C <b> 2 is arranged on the same axis as the output shaft 15, and selects transmission and interruption of torque between the secondary shaft 14 and the output shaft 15 of the continuously variable transmission 1. Is configured to perform automatically. The input shaft 9 and the primary shaft 13 of the continuously variable transmission 1 are directly connected to each other as the arrangement of the second clutch mechanism C2 is changed as described above with respect to the configuration shown in FIG.

Also in the power transmission device configured as shown in FIG. 6, the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the brake mechanism B are used when starting in the forward direction and during forward travel. And during reverse travel, they are engaged or released as shown in FIG. As in the case of the power transmission device shown in FIG. 1 described above, torque transmission via the torque transmission path mainly composed of the gear train 23 and the torque transmission path mainly composed of the continuously variable transmission 1 are performed. Torque transmission is performed. And it is made to act similarly to the power transmission device shown in FIG. 1, and the same effect can be acquired.

In the configuration shown in FIG. 6, the third clutch mechanism C3 is connected to the input shaft 9 and the drive gear 25 of the gear train 23 on the input shaft 9 in the same manner as the configuration of the power transmission device shown in FIG. Between. Therefore, as in the case of the power transmission device shown in FIG. 1 described above, the torque increased by the gear train 23 is not applied to the third clutch mechanism C3. Therefore, the size of the third clutch mechanism C3 can also be reduced in the configuration shown in FIG.

In the configuration shown in FIG. 6, the second clutch mechanism C <b> 2 is arranged on the so-called output side of the continuously variable transmission 1. Therefore, when the speed is reduced with the input shaft 9 and the output shaft 15 being connected via the gear train 23, the continuously variable transmission 1 may be disconnected from the output shaft 15 by the second clutch mechanism C2. it can. As a result, it is possible to avoid an excessive torque from acting on the continuously variable transmission 1 and improve the durability of the continuously variable transmission 1. That is, when the vehicle is decelerated with the first clutch mechanism C1 and the third clutch mechanism C3 engaged, torque based on the traveling inertia force of the vehicle acts on the output shaft 15. In that case, between the output shaft 15 and the secondary shaft 14 of the continuously variable transmission 1, the second clutch mechanism C2 is in a released state and is disconnected. Therefore, so-called reverse input torque at the time of deceleration is not applied to the continuously variable transmission 1. Therefore, it is possible to reduce the torque that unnecessarily acts on the continuously variable transmission 1 and to suppress unnecessary rotation. As a result, the durability of the continuously variable transmission 1 can be improved.

In the power transmission device shown in FIG. 7, the second clutch mechanism C2 and the third clutch mechanism C3 in the configuration shown in FIG. 1 are arranged on the same axis as the output shaft 15 together with the forward / reverse switching mechanism 16, and the other components are shown in FIG. The configuration is the same as the example shown in FIG. Therefore, only the parts different from FIG. 1 in the configuration of FIG. 7 will be described, and the same reference numerals as those in FIG.

In the example shown in FIG. 7, the second clutch mechanism C2 is arranged on the same axis as the output shaft 15 and has the secondary shaft 14 of the continuously variable transmission 1 as in the configuration of the power transmission device shown in FIG. And the output shaft 15 are configured to selectively transmit and block torque. Further, the third clutch mechanism C3 is arranged on the same axis as the output shaft 15 or the secondary shaft 14 in the same manner as the configuration of the power transmission device shown in FIG. Torque is transmitted to and disconnected from the carrier 21 of the mechanism 16 selectively. The drive gear 25 of the gear train 23 is integrated with the input shaft 9 as the arrangement of the second clutch mechanism C2 and the third clutch mechanism C3 is changed as described above with respect to the configuration shown in FIG. It is attached to rotate. Further, the input shaft 9 and the primary shaft 13 of the continuously variable transmission 1 are directly connected.

Also in the power transmission device configured as shown in FIG. 7, the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the brake mechanism B are used when starting in the forward direction and during forward travel. And during reverse travel, they are engaged or released as shown in FIG. As in the case of the power transmission device shown in FIG. 1 described above, torque transmission via the torque transmission path mainly composed of the gear train 23 and the torque transmission path mainly composed of the continuously variable transmission 1 are performed. Torque transmission is performed. And it is made to act similarly to the power transmission device shown in FIG. 1, and the same effect can be acquired.

Further, in the configuration shown in FIG. 7, the third clutch mechanism C3 is connected to the driven gear 28 of the gear train 23 and the forward / reverse switching mechanism on the output shaft 15 as in the configuration of the power transmission device shown in FIG. 16 carriers 21 are provided. Therefore, as in the case of the power transmission device shown in FIG. 4 described above, the rotational speed difference between the input side rotation member and the output side rotation member in the third clutch mechanism C3 is reduced. Therefore, also in the configuration shown in FIG. 7, the engagement control in the third clutch mechanism C3 can be easily performed. Further, the durability of the third clutch mechanism C3 can be improved.

In the configuration shown in FIG. 7, the second clutch mechanism C2 is arranged on the so-called output side of the continuously variable transmission 1, similarly to the configuration of the power transmission device shown in FIG. Therefore, as in the case of the power transmission device shown in FIG. 6 described above, when the speed is reduced with the input shaft 9 and the output shaft 15 being connected via the gear train 23, the second clutch mechanism C2 The step transmission 1 can be disconnected from the output shaft 15. Therefore, in the configuration shown in FIG. 7 as well, it is possible to avoid an excessive torque from acting on continuously variable transmission 1 and to improve durability of continuously variable transmission 1.

In the power transmission device shown in FIG. 8, the second clutch mechanism C2 in the configuration shown in FIG. 1 is arranged on the same axis as the output shaft 15 together with the forward / reverse switching mechanism 16, and the third clutch mechanism C3 is a gear train 23. The counter shaft 24 is disposed on the same axis. The rest of the configuration is the same as the example shown in FIG. Therefore, only the parts different from FIG. 1 in the configuration of FIG. 8 will be described, and the same reference numerals as those in FIG.

In the example shown in FIG. 8, the second clutch mechanism C2 is arranged on the same axis as the output shaft 15 in the same manner as the power transmission device shown in FIGS. Torque is transmitted and interrupted between the secondary shaft 14 and the output shaft 15 selectively. Further, the third clutch mechanism C3 is arranged on the same axis as the counter shaft 24 of the gear train 23 in the same manner as the configuration of the power transmission device shown in FIG. 5, and the counter drive of the counter shaft 24 and the gear train 23 is provided. Torque is selectively transmitted to and disconnected from the gear 27. The drive gear 25 of the gear train 23 is integrated with the input shaft 9 as the arrangement of the second clutch mechanism C2 and the third clutch mechanism C3 is changed as described above with respect to the configuration shown in FIG. It is attached to rotate. Further, the input shaft 9 and the primary shaft 13 of the continuously variable transmission 1 are directly connected.

Also in the power transmission device configured as shown in FIG. 8, the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the brake mechanism B are used for starting in the forward direction and for traveling forward. And during reverse travel, they are engaged or released as shown in FIG. As in the case of the power transmission device shown in FIG. 1 described above, torque transmission via the torque transmission path mainly composed of the gear train 23 and the torque transmission path mainly composed of the continuously variable transmission 1 are performed. Torque transmission is performed. And it is made to act similarly to the power transmission device shown in FIG. 1, and the same effect can be acquired.

In the configuration shown in FIG. 8, the second clutch mechanism C2 is arranged on the so-called output side of the continuously variable transmission 1, similarly to the configuration of the power transmission device shown in FIGS. Therefore, as in the case of the power transmission device shown in FIGS. 6 and 7, the second clutch mechanism is used when the input shaft 9 and the output shaft 15 are connected via the gear train 23 and the vehicle is decelerated. The continuously variable transmission 1 can be disconnected from the output shaft 15 by C2. Therefore, also in the configuration shown in FIG. 8, it is possible to avoid an excessive torque from acting on continuously variable transmission 1 and to improve durability of continuously variable transmission 1.

In the configuration shown in FIG. 8, the third clutch mechanism C3 is disposed on the same axis as the counter shaft 24 of the gear train 23, similarly to the configuration of the power transmission device shown in FIG. Accordingly, as in the case of the power transmission device shown in FIG. 5 described above, the torque is transmitted from the input shaft 9 to the counter shaft 24 through the gear pair of the drive gear 25 and the counter driven gear 26 in the gear train 23. By configuring as a speed reduction mechanism, the rotational speed difference between the input side rotation member and the output side rotation member in the third clutch mechanism C3 is reduced. Therefore, engagement control in the third clutch mechanism C3 can be easily performed. Further, the durability of the third clutch mechanism C3 can be improved.

When the third clutch mechanism C3 is arranged on the countershaft 24 as in the configuration shown in FIG. 8 and the configuration shown in FIG. 5, the counter drive gear 27 is connected to the countershaft 24, and Instead of being configured to release the connection, the third clutch mechanism C3 may be configured to connect the counter driven gear 26 to the counter shaft 24 and to release the connection. Alternatively, the third clutch mechanism C3 may be configured such that the counter driven gear 26 and the counter drive gear 27 are connected together, and are connected to the counter shaft 24, and the connection is released.

The power transmission device according to the present invention can be configured by a single pinion type planetary gear mechanism in place of the forward / reverse switching mechanism 16 in place of the double pinion type planetary gear mechanism described above. An example is shown in FIG. When the forward / reverse switching mechanism 16 in the present invention is configured using the single pinion type planetary gear mechanism 37, the sun gear 38 is an input element, the carrier 39 is a reaction force element, and the ring gear 40 is an output element. ing. Accordingly, the carrier 39 is provided with a brake mechanism B that selectively stops the rotation of the carrier 39. The driven gear 28 of the gear train 23 is connected to the sun gear 38, and the output shaft 15 is connected to the ring gear 40. Between the sun gear 38 and the ring gear 40, a first clutch mechanism C1 that selectively connects the sun gear 38 and the ring gear 40 is provided.

FIG. 10 shows an example of a collinear diagram (velocity diagram) representing the forward / reverse switching mechanism 16 constituted by the single pinion type planetary gear mechanism 37 as described above. In FIG. 10, the sun gear 38, the carrier 39, and the ring gear 40 are represented by straight lines parallel to each other. Among these straight lines, a straight line indicating the sun gear 38 and a straight line indicating the ring gear 40 are located at both left and right ends, and a straight line indicating the carrier 39 which is a reaction force element is arranged at the center thereof. When the distance between the straight line indicating the sun gear 38 and the straight line indicating the ring gear 18 is “1”, the distance between the straight line indicating the carrier 39 and the straight line indicating the ring gear 40 is the number of teeth of the sun gear 38 and the teeth of the carrier 39. It is set to a value corresponding to the ratio to the number (that is, gear ratio). The distance from the intersection of each straight line with the base line L0 indicates the number of rotations of each rotating element. The position with respect to the base line L0 indicates the rotation direction of each rotation element. Therefore, when the first clutch mechanism C1 is engaged, the planetary gear mechanism 37, that is, the entire forward / reverse switching mechanism 16 rotates as a whole, so that the rotational speed of each rotating element is indicated by a straight line Lf. . On the other hand, when the carrier 39 is fixed by the brake mechanism B, the rotation speed and the rotation direction of each rotating element are indicated by a straight line Lr. That is, the ring gear 40 rotates in the opposite direction with respect to the sun gear 38.

Thus, even when the forward / reverse switching mechanism 16 is configured by the single pinion type planetary gear mechanism 37, the forward / reverse switching mechanism 16 configured by the double pinion type planetary gear mechanism 37 is caused to function in the same manner. Can do. In addition, the apparatus can be simplified by using the single pinion type planetary gear mechanism 37 instead of the double pinion type planetary gear mechanism.

As described above, according to the power transmission device of the present invention, the entire forward / reverse switching mechanism 16 is integrated by connecting at least two rotating elements of the forward / reverse switching mechanism 16 with the first clutch mechanism C1. And the forward / reverse switching mechanism 16 and the output shaft 15 are in a state where power can be transmitted. In this state, the second clutch mechanism C2 is released and the third clutch mechanism C3 is engaged, whereby the continuously variable transmission 1 is disconnected from the output shaft 15 and the gear train 23 is moved forward and backward. It is connected to the output shaft 15 via That is, the input shaft 9 and the output shaft 15 are connected via the gear train 23 and the forward / reverse switching mechanism 16. In that case, the gear ratio by the gear train 23 is a gear ratio that cannot be set by the continuously variable transmission 1. That is, the speed ratio is larger than the maximum speed ratio in the continuously variable transmission 1 or smaller than the minimum speed ratio. Therefore, the gear ratio width as a whole of the power transmission device can be made wider than the gear ratio width that can be set by the continuously variable transmission 1.

Further, by engaging the brake mechanism B instead of the first clutch mechanism 1, the rotation of the reaction force element in the forward / reverse switching mechanism 16 is stopped, and as a result, the output element of the forward / reverse switching mechanism 16 becomes the input element. Rotate in the opposite direction. That is, the vehicle can travel backward. In this case, torque is transmitted from the output element of the forward / reverse switching mechanism 16 to the output shaft 15 via the third clutch mechanism C3 and the gear train 23. Therefore, the gear ratio set as a whole of the power transmission device in that case is a large gear ratio that cannot be set by the continuously variable transmission 1. That is, the speed ratio width as a whole of the power transmission device can be widened even during reverse travel.

In the power transmission device according to the present invention, the forward / reverse switching mechanism 16 is disposed on the same axis as the output shaft 15, and the output element of the forward / reverse switching mechanism 16 is coupled to the output shaft 15. As a result, for example, the inertial mass of the output shaft 15 becomes larger than when the forward / reverse switching mechanism 16 is disposed on the input shaft 9 or the counter shaft 24. Therefore, the output shaft 15 is not easily affected by vibrations, and so-called booming noise can be suppressed during low speed traveling by the continuously variable transmission 1.

Note that the positions of the first clutch mechanism C1, the second clutch mechanism C2, the third clutch mechanism C3, and the gears in the axial direction can be determined as appropriate in design. For example, the positions of adjacent constituent members among the constituent members in the specific examples described above can be interchanged in the axial direction.

Each of the specific examples described above is an example in which the gear ratio by the gear train 23 is made larger than the maximum gear ratio in the continuously variable transmission 1, but the present invention is basically a gear that cannot be set by the continuously variable transmission 1. What is necessary is just to be comprised so that ratio may be set with the gear train 23. FIG. Therefore, the speed ratio by the gear train 23 may be made smaller than the minimum speed ratio in the continuously variable transmission 1. If comprised in this way, when driving | running | working by driving the engine 2 with a low load, an engine speed can be made into a low speed compared with the case where a gear ratio is set with the continuously variable transmission 1. FIG. As a result, the fuel consumption of the vehicle can be further improved.

Further, in each of the specific examples described above, the configuration using the gear train 23 having one gear ratio (gear ratio) is shown, but the gear train in the present invention has two or more gear ratios (gear ratios). And a gear train that can select and set the gear ratios.

Claims

A continuously variable transmission that continuously changes a gear ratio between an input shaft to which torque output from a driving force source is input and an output shaft that outputs torque, and at least one that cannot be set by the continuously variable transmission In the vehicle power transmission device provided so that a gear train having a gear ratio can transmit torque between the input shaft and the output shaft, respectively.
A forward / reverse switching mechanism that performs a differential action by three rotating elements of an input element, an output element, and a reaction force element that rotates the input element and the output element in directions opposite to each other when rotation is stopped. Arranged on the same axis as the shaft, the output element and the output shaft are connected,
A first clutch mechanism for connecting at least any two of the three rotating elements; and a brake mechanism for stopping the rotation of the reaction force element;
The input shaft and the output element are connected via the continuously variable transmission, and torque is transmitted to a first torque transmission path from the input shaft to the output shaft via the continuously variable transmission. And a second clutch mechanism for shutting off is provided,
The input shaft and the input element are coupled via the gear train, and torque is transmitted and cut off in a second torque transmission path from the input shaft to the input element via the gear train. A power transmission device for a vehicle, wherein a third clutch mechanism is provided.
The gear train is configured to set a gear ratio larger than a maximum gear ratio of the continuously variable transmission or a gear ratio smaller than a minimum gear ratio of the continuously variable transmission by a plurality of gears. The power transmission device for a vehicle according to claim 1.
The continuously variable transmission has a drive side member that transmits torque from the input shaft and an output side member that outputs torque to the output shaft,
2. The second clutch mechanism is provided between the input shaft and the drive side member, and is configured to selectively connect the input shaft and the drive side member. Or a vehicle power transmission device according to 2;
The continuously variable transmission has a drive side member that transmits torque from the input shaft and an output side member that outputs torque to the output shaft,
2. The second clutch mechanism is provided between the output side member and the output shaft, and is configured to selectively connect the output side member and the output shaft. Or a vehicle power transmission device according to 2;
The vehicle power transmission device according to any one of claims 1 to 4, wherein each of the first clutch mechanism and the second clutch mechanism includes a friction clutch.
The vehicle power transmission device according to any one of claims 1 to 5, wherein the third clutch mechanism is constituted by a meshing clutch.
The gear train includes a drive gear disposed on the same axis as the input shaft, an intermediate shaft, a single idle gear provided on the intermediate shaft, or a plurality of idle gears that rotate together. Including a driven gear that transmits torque from the drive gear via the idle gear and is integrally connected to the input element;
The vehicle power transmission device according to any one of claims 1 to 6, wherein the third clutch mechanism is configured to perform connection and disconnection between the input shaft and the drive gear. .
The gear train includes a drive gear disposed on the same axis as the input shaft, an intermediate shaft, a single idle gear provided on the intermediate shaft, or a plurality of idle gears that rotate together. Including a driven gear that transmits torque from the drive gear via the idle gear and is integrally connected to the input element;
The vehicle power transmission device according to any one of claims 1 to 6, wherein the third clutch mechanism is configured to perform connection and disconnection between the driven gear and the input element. .
The gear train is disposed on the input shaft and connected to the input shaft; a driven gear integrally connected to the input element; an intermediate shaft; and the intermediate shaft; A first idle gear meshing with the drive gear and a second idle gear meshing with the driven gear;
The vehicle according to any one of claims 1 to 6, wherein the third clutch mechanism is configured to perform connection and disconnection between the first idle gear and the second idle gear. Power transmission device.
The forward / reverse switching mechanism includes a sun gear that is an external gear, a ring gear that is an internal gear arranged concentrically with the sun gear, a first pinion gear that meshes with the sun gear, the first pinion gear, and the ring gear 10. A double pinion type planetary gear mechanism comprising a second pinion gear meshing with each other and a carrier holding the first pinion gear and the second pinion gear so as to rotate and revolve. The power transmission device for a vehicle according to any one of the above.
The sun gear is connected to the continuously variable transmission and the output shaft,
The carrier is coupled to the gear train;
The vehicular power transmission device according to claim 10, wherein the ring gear is configured to be prevented from rotating by the brake mechanism.
The forward / reverse switching mechanism includes a sun gear that is an external gear, a ring gear that is an internal gear arranged concentrically with the sun gear, a pinion gear that meshes with the sun gear and the ring gear, and the pinion gear that rotates and revolves. The vehicle power transmission device according to any one of claims 1 to 9, further comprising a single pinion type planetary gear mechanism including a carrier that can be held.
The ring gear is connected to the continuously variable transmission and the output shaft,
The sun gear is coupled to the gear train;
The power transmission device for a vehicle according to claim 12, wherein the carrier is configured to be prevented from rotating by the brake mechanism.
The forward / reverse switching mechanism includes a plurality of rotating elements indicated by straight lines parallel to each other, and a collinear line indicating the rotation speed of each rotating element at a length from an intersection with a base line orthogonal to the straight line and a position relative to the base line According to the figure, including a planetary gear mechanism that can represent the respective rotation speeds of the input element, the output element, and the reaction force element;
The reaction force element is an element represented by a line located in the center of the collinear diagram, the input element is an element represented by either the left or right line in the collinear diagram, and The power transmission device for a vehicle according to any one of claims 1 to 13, wherein the output element is an element represented by one of left and right lines in the alignment chart.