JP2007247881A - Multi-stage transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-stage transmission capable of configuring so as to miniaturize and make light-weight at low cost. <P>SOLUTION: The multi-stage transmission is composed of a main shaft 1 and a counter shaft 4 which are mutually provided in parallel, a secondary shaft 2 which is relatively rotatably provided on concentric axis of the main shaft 1 and a sub-shaft 3 which is provided in parallel to the main shaft 1. The multi-stage transmission is also composed of a plurality of secondary-counter transmission paths 11, 14, 17 which are provided to make it possible to connect/disconnect respectively and which transmit to the counter shaft 3 by changing rotation of the secondary shaft 2 at mutually different transmission ratio, a first main-secondary transmission path 35 which breaks or contacts the main shaft 1 and the secondary shaft 2 and second main-secondary transmission paths 21, 3, 24 which are provided to make it possible to connect/disconnect and which transmit by changing rotation of the main shaft 1 via the sub-shaft 3 to the secondary shaft 2 and which rotate the counter shaft 2 in the same direction as when being transmitted via the first main-secondary transmission path 35. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-stage transmission that is configured by connecting and disconnecting a plurality of power transmission paths between a main shaft and a counter shaft, and is capable of setting a plurality of shift stages.

  As a multi-stage transmission capable of setting a plurality of shift stages, a form in which a plurality of gear trains are provided to be freely connected between parallel shafts (see, for example, Patent Document 1), a form having a planetary gear mechanism such as a Lepelche system, etc. Various forms are known. In any form, since any one of a plurality of power transmission paths between the input shaft (for example, main shaft) and the output shaft (for example, counter shaft) can be selectively set, these powers A plurality of connecting / disconnecting means for connecting / disconnecting the transmission path is provided. Such connecting / disconnecting means includes a hydraulically operated multi-plate clutch.

JP-A-3-292453

  In recent years, there has been a demand for further improvement in fuel economy performance of vehicles, and in order to set a desirable shift speed suitable for the running state, a multi-speed transmission capable of setting a large number of shift speeds, for example, five forward speeds or six forward speeds is provided. Is required. However, in the embodiment in which a plurality of gear trains are provided so as to be freely connected / disconnected between the parallel shafts, the number of connecting / disconnecting means such as gear trains and clutches increases as the settable gear speed increases. For this reason, there existed a possibility of causing the enlargement with respect to an axial direction etc., the increase in weight, and the cost increase. Further, when there is a restriction on the enlargement in the axial direction in view of the layout of the entire vehicle, the structure may be complicated, for example, the number of axes needs to be increased.

  In general, a configuration in which a plurality of gear trains are provided so as to be freely connectable and disconnectable between parallel shafts is considered to have a good transmission efficiency, although it is heavier than a configuration having a planetary gear mechanism. However, when the number of connecting / disconnecting means such as clutches increases with the increase in the number of stages, there is a further disadvantage in terms of weight, and there is a risk that drag may be generated and the superiority in terms of transmission efficiency may be lost. there were.

  In view of such problems, the present invention provides a multi-stage transmission capable of setting a plurality of shift speeds, which has good transmission efficiency and fuel efficiency, and is low in cost and small and light. With the goal.

  In order to achieve the above object, a multi-stage transmission according to the present invention is configured by connecting and disconnecting a plurality of power transmission paths between a main shaft and a counter shaft that are provided in parallel to each other, and any one of the power transmission paths. Is a multi-stage transmission capable of setting a predetermined shift stage from a plurality of shift stages, and a secondary shaft provided on the same axis as the main shaft so as to be relatively rotatable, and a sub-stage provided in parallel to the main shaft A plurality of secondary-counter transmission paths which are provided in a freely connectable / disconnectable manner and transmit the rotation of the secondary shaft to the countershaft by shifting the rotation of the secondary shaft to each other, and a first main which connects / disconnects the main shaft and the secondary shaft -Secondary transmission path and sub-shaft that can be connected and disconnected to rotate the main shaft Through speed change is transmitted to the secondary shaft, the first main - composed of the secondary transfer path - a second main rotating the countershaft in the same direction as when it was transmitted through the secondary transfer path.

  Further, it is preferable to share the driven element of the second main-secondary transmission path and the drive element of any one of the plurality of secondary-counter transmission paths. Furthermore, it is provided so as to be connectable / disconnectable, and the rotation of the main shaft is transmitted to the secondary shaft via the sub shaft, and the secondary shaft is rotated in the opposite direction with respect to when it is transmitted via the first main-secondary transmission path. It is preferable to have a third main-secondary transmission path to be used, and to share the driven element of the third main-secondary transmission path and the drive element of any one of the plurality of main-secondary transmission paths. .

  The first secondary-counter transmission path is configured by a first gear train including a first drive gear provided on the secondary shaft and a first driven gear provided on the countershaft and meshed with the first drive gear. A first connecting / disconnecting means for connecting / disconnecting one gear train to / from either the secondary shaft or the countershaft, wherein the second secondary-counter transmission path is provided on the secondary shaft; A second connecting / disconnecting means configured to be connected to the second shaft or the countershaft, the second gear train including a second driven gear provided on the countershaft and meshing with the gear; The third secondary-counter transmission path meshes with the third drive gear provided on the secondary shaft and the third drive gear. Comprising a third gear train comprising a third driven gear provided on the main shaft, and comprising third connecting / disconnecting means for connecting / disconnecting the third gear train to either the secondary shaft or the counter shaft. The secondary transmission path is provided in the fourth drive gear provided in the main shaft and the fourth gear train including the fourth driven gear provided in the sub shaft in mesh with the fourth drive gear, the sub shaft, and the sub shaft; The fifth drive gear and the fifth gear train, which is meshed with the fifth drive gear and is provided on the secondary shaft and is composed of a fifth driven gear, are provided with either the fourth gear train or the fifth gear train, the main shaft, It is preferable to include a fourth connecting / disconnecting device that connects / disconnects to either the sub shaft or the counter shaft.

  At this time, the second main-secondary transmission path and the first secondary-counter transmission path constitute a first power transmission path for setting the first forward speed, and the first main-secondary transmission path and the first The second power transmission path for setting the second forward speed is configured by the secondary-counter transmission path, and the third forward speed is set by the second main-secondary transmission path and the second secondary-counter transmission path. A fourth power transmission path for setting the fourth forward speed is configured by the first main-secondary transmission path and the second secondary-counter transmission path. The main-secondary transmission path and the third secondary-counter transmission path constitute a fifth power transmission path for setting the fifth forward speed, and the first main-secondary transmission path and the first Secondary - by a counter pathway may constitute a sixth power transmission path for setting the six forward speeds.

  The first driven gear is preferably connected to the countershaft via the first one-way clutch. It is preferable that the first drive gear is connected to the main shaft via the second one-way clutch, and the fourth connecting / disconnecting means is connected to the sub-shaft via the third one-way clutch.

  The second main-secondary transmission path and the first secondary-counter transmission path constitute a first power transmission path for setting the first forward speed, and the second main-secondary transmission path and the second A second power transmission path for setting the second forward speed is configured by the secondary-counter transmission path, and a third forward speed is set by the second main-secondary transmission path and the third secondary-counter transmission path. A third power transmission path is configured, and a fourth power transmission path for setting the fourth forward speed is configured by the first main-secondary transmission path and the first secondary-counter transmission path. The fifth power transmission path for setting the fifth forward speed is configured by the secondary transmission path and the second secondary-counter transmission path, and the first main-secondary transmission path and the third Secondary - by a counter pathway may constitute a sixth power transmission path for setting the six forward speeds.

  According to the multi-stage transmission according to the present invention configured as described above, power is transmitted through the secondary shaft regardless of which gear stage is set, and the two transmission paths are provided as the main-secondary transmission path. And a plurality of secondary-counter transmission paths. By combining these transmission paths, a plurality of power transmission paths with different gear ratios can be set. However, the number of power transmission paths provided between the secondary shaft and the countershaft should be half of the desired number of forward stages. Thus, a multi-stage transmission can be configured with a reduced size and weight. Since the secondary shaft is disposed coaxially with the main shaft, the overall size can be reduced as compared with a mode in which four axes are provided in parallel to each other.

  Further, by sharing the driven element of the second main-secondary transmission path and the driving element of any one of the plurality of secondary-counter transmission paths, the number of parts constituting the multi-stage transmission is reduced. Further cost reduction and reduction in size and weight can be achieved. Further, the power transmission via the third main-secondary transmission path enables the reverse gear to be set, but any one of the driven element of the third main-secondary transmission path and the plurality of secondary-counter transmission paths By sharing the drive element of the transmission path, the number of parts constituting the multi-stage transmission capable of setting the reverse speed can be reduced, and such a multi-stage transmission can be provided at a low cost, a small size, and a light weight.

  Note that six forward stages can be set by having three secondary-counter transmission paths. At this time, the three secondary-counter transmission paths can be configured from a gear train as usual. The second main-secondary transmission path includes a gear train for transmitting power from the main shaft to the sub shaft, and a gear train for transmitting power from the sub shaft to the secondary shaft. It is only necessary to provide one connection / disconnection means for contact. In this way, the number of gear trains and the number of connecting / disconnecting means required to be able to set six forward speeds can be reduced, and the cost, size and weight can be reduced, and the possibility of causing drag and the like is reduced. As a result, fuel efficiency is improved.

  Further, when the first to sixth power transmission paths for setting the first to sixth forward speeds are configured as described above, and the reduction ratio corresponding to the first speed stage is set to the second main-secondary transmission path, Half of the shift control between adjacent gears can be completed simply by switching the main-secondary transmission path. Therefore, the operation of the connecting / disconnecting means at the time of shifting can be simplified, and smooth shifting can be performed.

  Further, when the first one-way clutch is provided as described above, the first one-way clutch is engaged during acceleration of the first forward speed and the second forward speed, and it is not necessary to engage the first connecting / disconnecting means. . For this reason, since the first connecting / disconnecting means is sufficient to give the necessary torque capacity to the load at the time of deceleration of the second forward speed, the first connecting / disconnecting means can be reduced in size and cost-reduced multi-speed transmission. Can provide a machine. In addition, when the third one-way clutch is provided as described above, the third one-way clutch is released even if the fourth connection / disconnection means is engaged at the time of setting the gear position for releasing the fourth connection / disconnection means. Therefore, power transmission via the second main-secondary transmission path is not performed. Therefore, it is not necessary to severely set the engagement / disengagement timing of the fourth connecting / disconnecting means, and the shift control can be simplified. In addition, when the second one-way clutch is provided as described above, the engine speed can be at least up to the same rotational speed as that of the first drive gear, and the engine brake can be activated even when the third one-way clutch becomes free. It becomes possible.

  Further, when the first to sixth power transmission paths for setting the first to sixth forward speeds are configured as described above, and the reduction ratio corresponding to the third speed stage is set to the second main-secondary transmission path, Shifting between the first to third forward speeds and the fourth to sixth forward speeds can be completed by simply switching the secondary-counter transmission path. Therefore, the operation of the connecting / disconnecting means at the time of shifting can be simplified, and smooth shifting can be performed.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an automatic transmission 10 provided in a vehicle and capable of setting a plurality of shift stages as a first embodiment of a multi-stage transmission according to the present invention. The automatic transmission 10 includes a main shaft 1 connected to the output shaft of the engine 51, a secondary shaft 2 provided coaxially with the main shaft 1 and rotatable relative to the main shaft 1, and a main shaft 1. A sub shaft 3 provided in parallel to the main shaft 1 and a counter shaft 4 provided in parallel to the sub shaft 3, and three mains for transmitting the rotation of the main shaft 1 to the secondary shaft 2. The secondary transmission path includes three secondary-counter transmission paths for transmitting the rotation of the secondary shaft 2 to the counter shaft 4 and a plurality of clutches 31 to 35. The main shaft 1 and the secondary shaft 2 that are coaxially rotatable relative to each other have a double tube structure.

  Each of the first to fifth clutches 31 to 35 is a hydraulically operated friction multi-plate clutch mechanism, and includes a plurality of outer plates provided on the outer member and a plurality of inner plates provided on the inner member. The hydraulic chamber is configured to be engaged and disengaged by supplying hydraulic oil to an oil chamber provided inside. When both plates are engaged, the outer member and the inner member rotate integrally, and when both plates are released, the outer member and the inner member can rotate relative to each other.

  In the automatic transmission 10, the rotation of the main shaft 1 is transmitted to the secondary shaft 2 via any one of the three main-secondary transmission paths, and the rotation of the secondary shaft 2 is transmitted to the three secondary-counters. It is configured to be transmitted to the countershaft 4 via any one of the transmission paths. Different gear ratios are set in at least the first and second main-secondary transmission paths among the three main-secondary transmission paths. Different gear ratios are set in the three secondary-counter transmission paths.

  A final gear 5 is fixed to the counter shaft 4, and a differential mechanism 52 is connected to the final gear 5. The differential mechanism 52 is connected to the left and right wheels 54, 54 via the left and right accelerator shafts 53, 53. Are connected. The rotation transmitted to the countershaft 4 is transmitted to the wheels 54 and 54 via the final gear 5, the differential mechanism 52, and the accelerator shafts 53 and 53 to cause the vehicle to travel.

  The automatic transmission 10 has first to third gear trains 11, 14, and 17 for transmitting power from the secondary shaft 2 to the counter shaft 4, and power transmission from the main shaft 1 to the sub shaft 3. The fourth gear train 21 and fifth and sixth gear trains 24 and 27 for transmitting power from the sub shaft 3 to the secondary shaft 2 are provided.

  The first gear train 11 constitutes a first secondary-counter transmission path, and is engaged with the first drive gear 12 coupled to the secondary shaft 2 and the first drive gear 12 via the first one-way clutch 41. The first driven gear 13 is connected to the counter shaft 4. The first driven gear 13 is connected to an inner member of the first clutch 31 provided on the counter shaft 4, and the outer member of the first clutch 31 is coupled to the counter shaft 4. When the first clutch 31 is engaged, the first driven gear 13 rotates integrally with the counter shaft 4, the secondary shaft 2 and the counter shaft 4 are connected, and the rotation of the secondary shaft 2 is transmitted to the counter shaft 4. The When the first clutch 31 is released, the secondary shaft 2 and the countershaft 4 can be connected via the first one-way clutch 41. The first one-way clutch 41 becomes free when the rotation of the counter shaft 4 exceeds the rotation speed of the first driven gear 13.

  The second gear train 14 constitutes a second secondary-counter transmission path, and is engaged with the second drive gear 15 provided so as to be rotatable relative to the secondary shaft 2, and the second drive gear 15. 4 and a second driven gear 16 coupled to 4. The second drive gear 15 is connected to the inner member of the second clutch 32 provided on the secondary shaft 2, and the outer member of the second clutch 32 is coupled to the secondary shaft 2. When the second clutch 32 is engaged, the second drive gear 15 rotates integrally with the secondary shaft 2, the secondary shaft 2 and the counter shaft 4 are connected, and the rotation of the secondary shaft 2 is transmitted to the counter shaft 4. The When the second clutch 32 is released, the connection between the secondary shaft 2 and the counter shaft 4 is disconnected.

  The third gear train 17 constitutes a third secondary-counter transmission path, and the third drive gear 18 coupled to the secondary shaft 2 and the third drive gear 18 mesh with each other to rotate relative to the counter shaft 4. The third driven gear 19 is provided so as to be possible. The third driven gear 19 is connected to an inner member of a third clutch 33 provided on the counter shaft 4, and an outer member of the third clutch 33 is coupled to the counter shaft 4. When the third clutch 33 is engaged, the third driven gear 19 rotates integrally with the counter shaft 4, the secondary shaft 2 and the counter shaft 4 are connected, and the rotation of the secondary shaft 2 is transmitted to the counter shaft 4. The When the third clutch 33 is released, the connection between the secondary shaft 2 and the counter shaft 4 is disconnected.

  The main shaft 1 and the secondary shaft 2 are connected to a fifth clutch 35 that constitutes a first main-secondary transmission path. The main shaft 1 and the secondary shaft 2 can be connected and disconnected according to the engagement / disengagement state of the fifth clutch 35.

  The fourth gear train 21 includes a fourth drive gear 22 coupled to the main shaft 1 and a fourth driven gear 23 that meshes with the fourth drive gear 22 and is provided so as to be rotatable relative to the sub shaft 3. Become. The fourth driven gear 23 is connected to an inner member of a fourth clutch 34 provided on the sub shaft 3, and an outer member of the fourth clutch 34 is coupled to the sub shaft 3. When the fourth clutch 34 is engaged, the fourth driven gear 23 rotates integrally with the sub shaft 3, the main shaft 1 and the sub shaft 3 are connected, and the rotation of the main shaft 1 is transmitted to the sub shaft 3. The When the fourth clutch 34 is released, the connection between the main shaft 1 and the sub shaft 3 is disconnected.

  The fifth gear train 24 includes a fifth drive gear 25 provided so as to be rotatable relative to the sub shaft 3 and a third drive gear 18 of the third gear train 17 that meshes with the fifth drive gear 25. Thus, the third drive gear 18 functions as a drive element for the third gear train 17 and also as a driven element for the fifth gear train 24.

  The fourth gear train 21, the subshaft 3, and the fifth gear train 24 constitute a second main-secondary transmission path. The secondary shaft 2 rotates in the same direction with respect to the time through the first main-secondary transmission path by power transmission through the second main-secondary transmission path.

  The sixth gear train 27 includes a sixth drive gear 28 provided so as to be rotatable relative to the sub shaft 3, an idle gear 29 meshed with the sixth drive gear 28 and coupled to the idle shaft 6, and an idle gear. The second drive gear 15 of the second gear train 14 meshes with the second gear train 14. Thus, the second drive gear 15 functions as a drive element for the second gear train 14 and also functions as a driven element for the sixth gear train 27.

  The fourth gear train 21, the subshaft 3, and the sixth gear train 27 constitute a third main-secondary transmission path. The secondary shaft 2 rotates in the opposite direction with respect to the time through the first main-secondary transmission path by the power transmission through the third main-secondary transmission path.

  Each gear train is upstream of four trains of the fourth gear train 21, the first gear train 11, the second and sixth gear trains 14, 27, and the third and fifth gear trains 17, 24. They are arranged in order from the engine 51 side. The first clutch 31 is provided at a position overlapping the fourth gear train 21 in the axial direction on the upstream side of the first driven gear 13 of the countershaft 4, and the fourth clutch 34 is the fourth drive gear of the secondary shaft 2. 22 is provided at a position overlapping the final gear 5 with respect to the axial direction on the upstream side of 22. The second clutch 32 is provided on the downstream side of the second gear train 14. As a result, three rows of the fourth gear train 21, the first gear train 11, and the second and sixth gear trains 14 and 27 are arranged close to each other in the axial direction. The third clutch 33 is provided on the upstream side of the third gear train 17, and the fifth clutch 35 is provided on the downstream ends of the main shaft 1 and the secondary shaft 2, and the first to fifth clutches Reference numerals 31 to 35 are arranged in a zigzag manner between the main shaft 1, the sub shaft 3 and the counter shaft 4, and are made compact in the axial direction as a whole.

The gear ratio r of the first to fifth gear trains _{11, 14} , ₁₇ , ₂₁ , ₂₄ (the corresponding gear train is indicated by a suffix) is r ₁₁ > r ₁₄ · r ₂₁ · r ₂₄ > r ₁₄ > r ₁₄ > The relationship r ₁₇ · r ₂₁ · r ₂₄ > r ₁₇ is satisfied. That is, different gear ratios are set for the first to third secondary-counter transmission paths (first to third gear trains 11, 14, and 17). R ₂₁ and r ₂₄ indicate the gear ratio of the second main-secondary transmission path, but the secondary shaft 2 transmits the first main-secondary transmission by power transmission through the second main-secondary transmission path. It is decelerated and rotated with respect to the time through the transmission path.

  Further, the subshaft 3 selects which of the second main-secondary transmission path and the third main-secondary transmission path is established between the fifth drive gear 25 and the sixth drive gear 28. A selector 46 is provided. The fifth drive gear 25 and the sixth drive gear 28 are formed with extending portions 25a, 28a extending in the direction of the selector 46, respectively. The selector 46 is configured to have a rotating body that rotates integrally with the subshaft 3, and operates so as to engage with any one of the extending portions 25a and 28a. When the selector 46 is engaged with the extending portion 25 a of the fifth drive gear 25, the fifth drive gear 25 rotates integrally with the sub shaft 3, the sixth drive gear 26 rotates idly, and the selector 46 is connected to the sixth drive gear 28. When engaged with the extending portion 28a, the sixth drive gear 28 rotates integrally with the subshaft 3, and the fifth drive gear 25 idles.

  The vehicle is provided with a shift lever near the driver's seat, and the operation state of the selector 46 is switched by operating the shift lever. When the shift lever is operated to the position for setting the forward range, the selector 46 is engaged with the extending portion 25a of the fifth drive gear 25, and when the shift lever is operated to the position for setting the reverse range, the selector 46 is Engage with the extension 28 a of the drive gear 28. In addition, by operating the shift lever, a neutral range for setting the automatic transmission 10 to the neutral state can be set in addition to the forward and reverse ranges as in a general vehicle. It should be noted that the selector 46 is engaged with the extending portion 25a of the fifth drive gear 25 when being operated to the position for setting the neutral range.

  Further, the automatic transmission 10 is provided with a hydraulic circuit (not shown) for supplying hydraulic pressure to the first to fifth clutches 31 to 35 and a transmission control device (not shown) for automatically changing the gear position. ing. The shift control device determines a target shift stage based on input information from sensors provided in each part of the vehicle and a shift schedule stored in a built-in memory, and the determined target shift stage is set. The control signal is output to the solenoid valve constituting the hydraulic circuit to drive the valve to switch the hydraulic pressure supply path to the first to fifth clutches 31 to 35, and the first to fifth clutches 31 to 35 are engaged / disengaged. To control. The power transmission path established as appropriate is changed according to the engagement / disengagement state of the first to fifth clutches 31 to 35, and a predetermined gear position is set.

  By this shift control device, a command for upshifting or downshifting the shift stage to the target shift stage is generated in accordance with the vehicle state or the driver's intention of steering, and the shift control is performed. As a sensor for outputting input information to the speed change control device, a vehicle speed sensor for detecting the vehicle speed, an accelerator pedal sensor for detecting the opening degree of the accelerator pedal, a shift position sensor for detecting the position of the shift lever, and an engine rotation speed are detected. There are engine rotation speed sensors and the like.

  FIG. 2 shows the relationship between the shift speeds that can be set by the automatic transmission 10 and the engagement / disengagement states of the first to fifth clutches 31 to 35 when the respective shift speeds are set. The automatic transmission 10 can set a total of seven shift stages including six forward speeds and one reverse speed. Hereinafter, the switching of the engagement / disengagement state of the first to fifth clutches 31 to 35 at the time of shifting and the power transmission path established when each gear stage is set will be described.

  When the shift lever is operated to a position where the neutral range is set, all of the first to fifth clutches 31 to 35 are released. At this time, a power transmission path is not established between the main shaft 1 and the counter shaft 4, and the automatic transmission 10 becomes neutral.

When the shift lever is operated to a position for setting the forward range, the selector 46 is engaged with the extending portion 25a of the fifth drive gear 25 and the fourth clutch 34 is engaged. As a result, the fourth driven gear 23 is coupled to the sub shaft 3. The first driven gear 13 is connected to the counter shaft 4 via the first one-way clutch 41. At this time, a first power transmission path constituted by the second main-secondary transmission path and the first secondary-counter transmission path is established between the main shaft 1 and the counter shaft 4, and r ₁₁ , r ₂₁ , the first forward speed gear ratio corresponding to the r ₂₄ (Low) is set. Normally, the first forward speed is set at the start of starting.

  Thus, when the first forward speed is set, during acceleration, the rotation of the first driven gear 13 is transmitted to the counter shaft 4 via the first one-way clutch 41. Further, at the time of deceleration at which the first forward speed is set, the first one-way clutch 41 is engaged and transmitted to the first driven gear 13, and the engine brake is applied via the second main-secondary transmission path. Be able to.

When a command to upshift is generated when the first forward speed is set, the fourth clutch 34 is released, and the first and fifth clutches 31 and 35 are engaged. As a result, the first driven gear 13 is coupled to the counter shaft 4, and the main shaft 1 and the secondary shaft 2 are coupled. At this time, the first main between the main shaft 1 and the counter shaft 4 - Secondary pathway and the first secondary - second power transmission path composed of the counter transmission path is established, the shift corresponding to r ₁₁ The second forward speed (2nd) of the ratio is set.

  Here, when the second forward speed is set, during acceleration, the rotation of the first driven gear 13 is counter-shafted via the first one-way clutch 41 in the same manner as when the first forward speed is established. 4 is transmitted. Thus, during acceleration, the first one-way clutch 41 allows the first clutch 31 to be ignored for power transmission. However, since power cannot be transmitted by the first one-way clutch 41 during deceleration, it is necessary to engage the first clutch 31 that directly connects the first driven gear 13 and the counter shaft 4. That is, the first clutch 31 only needs to have a torque capacity that allows power to be transmitted during this deceleration.

When a command for upshifting is generated when the second forward speed is set, the first and fifth clutches 31 and 35 are released, and the second and fourth clutches 32 and 34 are engaged. As a result, the coupling of the first driven gear 13 to the counter shaft 4 and the coupling of the main shaft 1 and the secondary shaft 2 are released, the second drive gear 15 is coupled to the secondary shaft 2, and the fourth driven gear 23 is connected to the sub-shaft. Coupled to the shaft 3. At this time, a third power transmission path composed of a second main-secondary transmission path and a second secondary-counter transmission path is established between the main shaft 1 and the counter shaft 4, and r ₁₄ , r ₂₁ , forward speed ratio corresponding to r ₂₄ 3 speed (3rd) is set.

  Thus, when the second gear train 14 (which is the same as the third gear train 17) having a gear ratio smaller than that of the first gear train 11 is established as the power transmission path to the countershaft 4, the first one-way clutch 41 is Become free. Accordingly, when the second secondary-counter transmission path (the same applies to the third secondary-counter transmission path) is established, the power transmission by the first gear train 11 is irrelevant in setting the gear position.

When a command for upshifting is generated when the third forward speed is set, the second clutch 32 is kept engaged, the fourth clutch 34 is released, and the fifth clutch 35 is engaged. As a result, the main shaft 1 and the secondary shaft 2 are coupled again. Thus, the first main between the main shaft 1 and the counter shaft 4 - Secondary transmission path and the second secondary - fourth power transmission path composed of the counter transmission path is established, the shift corresponding to r ₁₄ The fourth forward speed (4th) of the ratio is set.

When an upshift command is generated when the fourth forward speed is set, the second and fifth clutches 32 and 35 are released, and the third and fourth clutches 33 and 34 are engaged. Thereby, the coupling between the main shaft 1 and the secondary shaft 2 is released again. As a result, a fifth power transmission path composed of the second main-secondary transmission path and the third secondary-counter transmission path is established between the main shaft 1 and the countershaft 4, and r ₁₇ , r ₂₁ , A forward fifth speed (5th) with a gear ratio corresponding to r ₂₄ is set.

When a command for upshifting is generated when the fifth forward speed is set, the third clutch 33 is kept engaged, the fourth clutch 34 is released, and the fifth clutch 35 is engaged. Thereby, the coupling between the fourth driven gear 23 and the sub shaft 3 is released, and the main shaft 1 and the secondary shaft 2 are coupled again. Thus, the first main between the main shaft 1 and the counter shaft 4 - Secondary transmission path and the third secondary - sixth power transmission path composed of the counter transmission path is established, the shift corresponding to r ₁₇ The sixth forward speed (6th) of the ratio is set.

  When any of the 6th forward speed and the 2nd forward speed is set, if a downshift command is generated, the reverse engagement control is performed to reverse the upshift, and the first low speed gear stage. Is set.

  In addition, the shift control device provided in the automatic transmission 10 has a greater driving force such as a greater amount of depression of the accelerator pedal, for example, when a shift speed higher than the second forward speed is set. Is determined to be transmitted to the wheels 54, 54, it is configured to perform control for setting a two-speed low speed to the set speed.

  When a command for downshifting is generated in this way when the sixth forward speed is set, the third clutch 33 is released and the fifth clutch 35 is engaged. As a result, the fourth power transmission path is established instead of the sixth power transmission path, and the fourth forward speed is set. If such a command is generated when the fourth forward speed is set, the fifth clutch 35 is maintained engaged and the first clutch 31 is engaged. Thereby, the second power transmission path is established instead of the fourth power transmission path, and the second forward speed is set.

  If such a command is generated when the fifth forward speed is set, the fourth clutch 34 is maintained engaged, the third clutch 33 is released, and the second clutch 32 is engaged. As a result, the third power transmission path is established instead of the fifth power transmission path, and the third forward speed is set. If such a command is generated when the third forward speed is set, the fourth clutch 34 is maintained engaged and the second clutch 32 is released. As a result, the first power transmission path is established instead of the third power transmission path, and the first forward speed is set.

When the shift lever is operated to a position for setting the reverse range, the selector 46 is engaged with the extending portion 28a of the sixth drive gear 28 and the fourth clutch 34 is engaged. As a result, the fourth driven gear 23 is coupled to the sub shaft 4. At this time, a seventh power transmission path including a third main-secondary transmission path and a second secondary-counter transmission path is established between the main shaft 1 and the countershaft 4. When power is transmitted through the seventh power transmission path, the countershaft 4 rotates in the direction opposite to that when the forward 1st to 6th speed is set. The reverse speed (Rvs) is set by establishing the seventh power transmission path. The sixth gear train 27 and the selector 46 constitute a reverse mechanism 45 of the automatic transmission 10. The gear ratio of the reverse gear, when the gear ratio of the sixth gear train and r _27, which corresponds to _{r 14 · r 21 · r 27} .

  The automatic transmission 10 having the above-described configuration transmits power through the secondary shaft 2 regardless of which gear stage is set. In setting the forward gear, the main-secondary transmission path has two transmission paths, and the secondary-counter transmission path has three transmission paths. Therefore, the automatic transmission 10 can set six power transmission paths having different speed ratios by combining these transmission paths. That is, half of the gear train for the desired number of forward gears is provided between the secondary shaft 2 and the counter shaft 4, and two gear trains for setting a transmission path via the sub shaft 3 are provided for the main shaft 1 and the sub shaft. A plurality of power transmission paths corresponding to a desired number of forward gears can be set.

  For this reason, the automatic transmission which can reduce the number of gear trains and can set many gear stages can be comprised. Furthermore, by reducing the number of gear trains, the number of clutches that connect and disconnect the power transmission path can also be reduced, and the possibility of dragging can be reduced. For this reason, an automatic transmission that is improved in fuel efficiency by setting an appropriate gear position from a large number of gear speeds according to the vehicle state can be reduced in size and weight without reducing transmission efficiency. Can be configured at cost. Further, since the power transmission is performed by the gear train provided between the parallel shafts, an automatic transmission with higher transmission efficiency can be provided as compared with the planetary gear type in which a large number of gears can be set similarly. Although the automatic transmission 10 is configured to have four parallel axes, the main shaft 1 and the secondary shaft 2 are coaxially disposed, so that the automatic transmission 10 is compared with a configuration in which the four axes are provided in parallel to each other. The size can be reduced.

  Further, the driven element of the fifth gear train 24 that transmits power from the sub shaft 3 to the secondary shaft 2 and the drive element of the third gear train 17 that transmits power from the secondary shaft 2 to the counter shaft 4 are shared. . For this reason, the number of parts constituting the automatic transmission can be reduced, and the automatic transmission can be further reduced in size and weight. Further, an idle gear 29 is provided in the sixth gear train 27 for transmitting power from the sub shaft 3 to the secondary shaft 2, and the reverse mechanism 45 is configured by the sixth gear train 27. The driven element of the sixth gear train 27 and the drive element of the second gear train 14 for transmitting power from the secondary shaft 2 to the countershaft 4 are shared. For this reason, the number of parts constituting the automatic transmission capable of setting the reverse gear can be reduced.

  Further, a reduction ratio corresponding to the first gear is set in the second main-secondary transmission path. As a result, half of the shift control between adjacent gears can be completed simply by switching the main-secondary transmission path by switching the engagement / disengagement state of the fourth clutch 34 and the fifth clutch 35. Simplification of the shift control by the control device is achieved. Furthermore, when shifting to the two-stage low speed side, there is no need to switch the main-secondary transmission path, and a multi-stage transmission with good response to an acceleration request or the like can be provided.

  Further, the first one-way clutch 41 is engaged only at the time of acceleration of the first forward speed and the second forward speed, and even if the first clutch 31 is released, the first one-way clutch 41 is connected to the counter shaft 4 via the first secondary-counter transmission path. Power can be transmitted. Therefore, the first clutch 31 is sufficient if it has the necessary torque capacity with respect to the load at the time of deceleration of the second forward speed. Therefore, the first clutch 31 can be reduced in size and can be provided at a lower cost. .

  FIG. 3 shows a skeleton diagram of the automatic transmission 90 in the second embodiment. Except for the addition of the second one-way clutch 42 and the third one-way clutch 43, the configuration is the same as that of the automatic transmission 10 in the first embodiment, and the same members are denoted by the same reference numerals. .

  The first drive gear 12 coupled to the secondary shaft 2 is coupled to the main shaft 1 via the second one-way clutch 42. In the first configuration example, the outer member of the fourth connecting / disconnecting means 34 is connected to the sub shaft 3 via the third one-way clutch 43, while being connected to the sub shaft 3. The second one-way clutch 42 becomes free when the rotational speed of the main shaft 1 becomes faster than that of the first drive gear 12. The third one-way clutch 43 becomes free when the rotation speed of the sub shaft 3 becomes faster than that of the fourth driven gear 23. The reduction gear ratio of the fifth gear train 24 is set larger than the reduction gear ratio of the fourth gear train 21.

  With this configuration, the fifth clutch 35 is engaged when shifting from the first forward speed to the second forward speed, from the third forward speed to the fourth forward speed, and from the fifth forward speed to the sixth forward speed. When the release timing of the fourth clutch 34 is delayed with respect to the timing and the fourth clutch 34 and the fifth clutch are both engaged, the sub shaft 3 is connected to the main shaft via the fifth gear train 24. 1 is accelerated and transmitted, and the rotation of the main shaft 1 is transmitted to the outer member of the fourth clutch 34 via the fourth gear train 21, so that the third one-way clutch 43 becomes free. Therefore, the engagement state of the fourth clutch 34 is irrelevant in setting the above-described shift speed. For this reason, it is not necessary to set a severe timing for clutch change at the time of shifting. Furthermore, the number of clutches that can be engaged / disengaged at the time of shifting can be reduced by keeping the fourth clutch 34 always engaged.

  Since the third one-way clutch 43 is added and becomes free so that the engine brake cannot be obtained. By adding the second one-way clutch 42, the engine rotation is at least at the first drive gear. 12 so that the rotational speed is the same as that of No. 12. Thereby, it is possible to achieve a configuration in which the engine brake acts at the second forward speed or the like.

  The multi-stage transmission according to the present invention is not limited to the configuration of the above embodiment, and can be changed as appropriate. For example, the first to third clutches 31 to 33 need only be provided so that the first to third secondary-counter transmission paths can be connected and disconnected, and either the drive gear or the driven gear can be connected or disconnected. It may be done. Similarly, the 4th clutch 34 should just be provided so that connection and disconnection of the 2nd main-secondary transmission path is possible. Further, the arrangement of the gear train is not limited to that shown in the figure, and can be changed as appropriate. Further, the drive element sharing the driven element of the fifth gear train 24 is not limited to the third gear train 17, and the drive element sharing the driven element of the sixth gear train 27 is not limited to the second gear train 14.

  Further, the third one-way clutch 43 can connect and disconnect the second main-secondary transmission path based on the rotational speed of the sub shaft 3 and the rotational speed of the fourth gear train 21 or the fifth gear train 24 at least during forward travel. As long as it is arranged at any location, it may be configured to be interposed between the fifth drive gear 25 and the extending portion 25a. If it is provided at this location, power transmission is irrelevant when the reverse gear is set, but during forward travel, it can be acted in the same way as in the above configuration example, and it is interposed between the outer member of the clutch and the shaft. It can be attached with a simpler structure than installing.

In addition, the power transmission via the sub shaft 3 is configured to reduce the speed ratio corresponding to one stage to perform the power transmission, but the power transmission is performed by reducing the speed ratio corresponding to the third stage. You may comprise so that it may be performed. That is, the gear ratio r of the first to fifth gear trains _{11, 14, 17} , _{21, and 24} is changed so as to satisfy the relationship of r ₁₇ × r ₂₁ × r ₂₄ > r ₁₁ > r ₁₄ > r _17. Also good. At this time, the second main-secondary transmission path and the first secondary-counter transmission path constitute a power transmission path for setting the first forward speed, and the second main-secondary transmission path and the second secondary- A power transmission path for setting the second forward speed is configured by the counter transmission path, and a power transmission path for setting the third forward speed is configured by the second main-secondary transmission path and the third secondary-counter transmission path. The first main-secondary transmission path and the first secondary-counter transmission path constitute a power transmission path for setting the fourth forward speed, and the first main-secondary transmission path and the second secondary-counter A power transmission path for setting the fifth forward speed is configured by the transmission path, and the first main-secondary transmission path and the third secondary-cow Power transmission path to set the sixth forward speed by the motor pathway is formed. Even if it is configured so that the shift speed is set in this way, the main-secondary transmission path is not changed in the shift between the first to third forward speeds and the fourth to sixth forward speeds. It can be completed only by switching the first to third secondary-counter transmission paths, and the shift control by the shift control device can be simplified.

  In addition, it is always configured so that the lowest speed is not set at the start of starting and a speed that is one speed higher than the lowest speed is set, and shifting is performed between this speed and the highest speed. You may comprise so that control may be performed. At this time, for example, an operation means such as a button switch may be provided on the shift lever, and the minimum speed may be set only when the shift control device determines that the operation means has been operated. At this time, by setting the reduction ratio of the minimum speed stage to be larger than the normal minimum speed stage, a low-cost, compact and lightweight transmission that can cope with an emergency that requires a particularly large driving force, such as towing, is achieved. Can be provided. In addition, since a large number of gears can be set as described above, even if the minimum gear is set as a gear set in an emergency and the gear shift control during normal driving is performed at the remaining gears, The possibility of causing deterioration in fuel consumption performance and drivability during traveling is reduced.

  Further, although three secondary-counter transmission paths are provided so that six forward speeds can be set, the present invention is not necessarily limited to this, and can be changed as appropriate according to the characteristics of the vehicle to be mounted. For example, by adding one gear train, four secondary-counter transmission paths may be provided so that seven or eight forward speeds can be set, or two secondary gears can be set by reducing one gear train. -A counter transmission path may be provided so that three or four forward speeds can be set.

  Further, a starting element such as a torque converter may be interposed between the engine 51 and the main shaft 1. Further, the connecting / disconnecting means according to the present invention is a hydraulically operated clutch, and the multi-stage transmission according to the present invention includes a hydraulic circuit that supplies the hydraulic pressure to the clutch, and a shift control device that drives and controls the valves that constitute the hydraulic circuit. However, the multi-stage transmission according to the present invention is not necessarily limited to such a form. For example, the connecting / disconnecting means may be configured to be manually operable, and the multi-stage transmission according to the present invention may be a manual transmission.

1 is a skeleton diagram of an automatic transmission according to a first embodiment shown as an example of a multi-stage transmission according to the present invention. It is a table | surface which shows the relationship between the gear stage set by the said automatic transmission, and the engagement / disengagement state of a clutch when each gear stage is set. It is a skeleton figure of the automatic transmission of 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main shaft 2 Secondary shaft 3 Sub shaft 4 Counter shaft 10,90 Automatic transmission 11 1st gear train (1st secondary-counter transmission path)
14 Second gear train (second secondary-counter transmission path)
17 Third gear train (third secondary-counter transmission path)
21 Fourth gear train (second and third main-secondary transmission paths)
24 fifth gear train (second main-secondary transmission path)
27 Sixth gear train (third main-secondary transmission path)
31 1st clutch (1st connection / disconnection means)
32 Second clutch (second connecting / disconnecting means)
33 3rd clutch (3rd connection / disconnection means)
34 Fourth clutch (fourth connecting / disconnecting means)
35 fifth clutch (first main-secondary transmission path)
41 First one-way clutch 42 Second one-way clutch 43 Third one-way clutch

Claims (8)

A plurality of power transmission paths are provided between the main shaft and the counter shaft provided in parallel to each other so as to be freely connectable and disconnectable. One of the power transmission paths is established to set a predetermined gear position, A multi-stage transmission that shifts the rotation of the shaft in accordance with the gear ratio of the power transmission path and transmits it to the counter shaft;
A secondary shaft provided so as to be relatively rotatable on the same axis as the main shaft;
A sub shaft provided in parallel with the main shaft;
A first main-secondary transmission path connecting and disconnecting the main shaft and the secondary shaft;
A second main-secondary transmission path that is provided so as to be connectable and disconnectable, and that shifts the rotation of the main shaft via the sub-shaft and transmits it to the secondary shaft;
A multi-stage transmission comprising a plurality of secondary-counter transmission paths, each provided so as to be freely connectable and disconnectable, and transmitting the rotation of the secondary shaft to the countershaft at a different speed ratio.   The multi-stage transmission according to claim 1, wherein a driven element of a main-secondary transmission path and a drive element of any one of the plurality of secondary-counter transmission paths are shared. Provided to be connectable / disconnectable, the rotation of the main shaft is transmitted to the secondary shaft via the sub-shaft, and the secondary shaft is rotated in a direction opposite to that transmitted via the main-secondary transmission path. A third main-secondary transmission path
3. The driven element of the third main-secondary transmission path and the drive element of any one of the plurality of main-secondary transmission paths are shared. Multi-stage transmission. Three secondary-counter transmission paths are provided;
The first secondary-counter transmission path is a first gear train including a first drive gear provided on the secondary shaft and a first driven gear provided on the counter shaft in mesh with the first drive gear. A first connecting / disconnecting unit configured to connect / disconnect the first gear train to either the secondary shaft or the counter shaft;
The second secondary-counter transmission path is a second gear train comprising a second drive gear provided on the secondary shaft and a second driven gear provided on the counter shaft in mesh with the second drive gear. Comprising a second connecting / disconnecting means configured to connect / disconnect the second gear train to either the secondary shaft or the counter shaft;
The third secondary-counter transmission path is a third gear train including a third drive gear provided on the secondary shaft and a third driven gear provided on the countershaft and meshed with the third drive gear. Comprising a third connecting / disconnecting means configured to connect / disconnect to either the secondary shaft or the counter shaft;
A fourth gear train comprising a fourth drive gear provided on the main shaft and a fourth driven gear provided on the sub shaft in mesh with the fourth drive gear provided on the main shaft; The fourth gear train is composed of a subshaft and a fifth gear train comprising a fifth drive gear provided on the subshaft and a fifth driven gear meshed with the fifth drive gear and provided on the secondary shaft. And a fourth connecting / disconnecting means for connecting / disconnecting any one of the first gear train and the fifth gear train to any one of the main shaft, the sub shaft, and the counter shaft. The multi-stage transmission according to any one of the above. The second main-secondary transmission path and the first secondary-counter transmission path constitute a first power transmission path for setting the first forward speed,
The first main-secondary transmission path and the first secondary-counter transmission path constitute a second power transmission path for setting the second forward speed,
The second main-secondary transmission path and the second secondary-counter transmission path constitute a third power transmission path for setting the third forward speed,
The first main-secondary transmission path and the second secondary-counter transmission path constitute a fourth power transmission path for setting the fourth forward speed,
The second main-secondary transmission path and the third secondary-counter transmission path constitute a fifth power transmission path for setting the fifth forward speed,
5. The multi-stage according to claim 4, wherein the first main-secondary transmission path and the third secondary-counter transmission path constitute a sixth power transmission path for setting the sixth forward speed. transmission.   The multi-stage transmission according to claim 4 or 5, wherein the first driven gear is connected to the counter shaft via a first one-way clutch.   The first drive gear is connected to the main shaft via a second one-way clutch, and the fourth connecting / disconnecting means is connected to the sub-shaft via a third one-way clutch. Item 7. The multi-stage transmission according to any one of Items 4 to 6. The second main-secondary transmission path and the first secondary-counter transmission path constitute a first power transmission path for setting the first forward speed,
The second main-secondary transmission path and the second secondary-counter transmission path constitute a second power transmission path for setting the second forward speed,
The second main-secondary transmission path and the third secondary-counter transmission path constitute a third power transmission path for setting the third forward speed,
The first main-secondary transmission path and the first secondary-counter transmission path constitute a fourth power transmission path for setting the fourth forward speed,
The first main-secondary transmission path and the second secondary-counter transmission path constitute a fifth power transmission path for setting the fifth forward speed,
5. The multi-stage according to claim 4, wherein the first main-secondary transmission path and the third secondary-counter transmission path constitute a sixth power transmission path for setting the sixth forward speed. transmission.

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