JP2010249261A - Automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively reduce the load through a thrust force generated in a gear or member of an automatic transmission. <P>SOLUTION: The automatic transmission 1 includes a first and a second connecting members M1 and M2 transmitting an input from an input shaft 10 to a minor-diameter sun gear SS and a major-diameter sun gear LS of a gear shifting planetary mechanism G2 through clutches C1 and C3, and a third connecting member M3 connected to the ring gear FR of a step-up planetary gear mechanism G1. In the fifth and sixth speed steps in which the step-up rotation of the planetary mechanism G1 is transmitted to the planetary mechanism G2, the torsional direction of a helical gear is set so that a thrust force F1 generated in the ring gear FR of the planetary mechanism G1 and a thrust force F2 generated in the major-diameter sun gear LS of the planetary mechanism G2 have the same direction. Thus, the load placed on bearings BG4-BG6 or the like which support the first to third connecting members M1-M3 in high-speed stage can be effectively reduced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an automatic transmission mounted on a vehicle such as an automobile, and more particularly to an automatic transmission having a structure for reducing a load applied to an internal structure such as a bearing from an element such as a gear.

  In an automatic transmission equipped with a planetary gear, a helical gear is used for each gear (sun gear, ring gear, etc.) constituting the planetary gear in order to reduce gear noise. By using a helical gear, the gear meshing rate can be increased and gear noise can be reduced. On the other hand, however, there is a problem that opposite thrust forces are generated in the ring gear and the sun gear.

  As a technique for dealing with the thrust force generated in such a helical gear, an automatic transmission described in Patent Document 1 has been proposed. This automatic transmission includes a speed reduction planetary gear that is connected to an input shaft and fixes a reaction force element to output a speed reduction rotation to an output element, and a planetary gear that outputs a speed reduction rotation from the speed reduction rotation from the speed reduction planetary gear. An automatic transmission that achieves multi-stage shifting by means of a set, having a common transmission path through which thrust forces generated respectively by the ring gear of the planetary gear for reduction and the sun gear of the planetary gear set are transmitted, the common transmission path The twisting direction of the ring gear and the sun gear is set so that the direction of the thrust force of the ring gear and the direction of the thrust force of the sun gear are different from each other during the first speed drive.

  According to the automatic transmission of Patent Document 1, since the thrust forces of the speed reduction planetary gear and the planetary gear set are set in different directions at the time of the first speed driving in which the driving force is the largest and the load by the thrust force is applied, the thrust is set differently. The load applied to the member that receives the force can be reduced.

JP 2000-304107 A

  The automatic transmission of Patent Document 1 is a reduction type multi-stage transmission including a reduction planetary gear, and a shift stage in which a load is input to the transmission planetary gear is a low-speed stage shift stage. Therefore, a low bearing load can be realized with the above configuration. However, in the speed-up type multi-speed transmission provided with the speed-up planetary gear instead of the speed reduction planetary gear of Patent Document 1, the speed stage where the speed-up rotation is input to the speed-change planetary gear is on the high speed side. In addition, the relative rotational speed of each component such as a gear supported by the bearing is significantly increased as compared with a reduction type multi-stage transmission, and the components on both sides of the bearing are in a high differential rotation state at a high speed. Therefore, in the same thrust load direction (helical gear twist direction) as in Patent Document 1, a large load acts on the bearing at the high speed stage. Therefore, it is necessary to give the bearing and the case high load-bearing performance, and there is a problem in that the size and cost of the bearing are increased. In addition, when a large load acts on a bearing or the like due to high-difference rotation, there is a problem that the energy loss associated therewith increases.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an automatic transmission including a speed-up planetary mechanism that inputs speed-up rotation to a speed-change planetary mechanism, by a component having a high differential rotation. It is to effectively reduce the generated load.

  An automatic transmission according to the present invention for solving the above-described problems is provided with an output element (FS) by receiving an input from an input element (FS) connected to an input shaft (10) and fixing a reaction force element (FS). FR), a speed-up planetary mechanism (G1) that outputs speed-up rotation, and a speed-change planetary mechanism (G2) that outputs speed-up rotation by receiving speed-up rotation from the speed-up planetary mechanism (G1). In the automatic transmission (1) that achieves a shift, the input from the input shaft (10) is transmitted to the first element (SS) of the shift planetary mechanism (G2) via the first friction engagement element (C1). One member (M1) and a second member (M2) for transmitting the input from the input shaft (10) to the second element (LS) of the transmission planetary mechanism (G2) via the second friction engagement element (C3). And the second member (M2) to the stationary member (30) A third friction engagement element (B1) for determining, a third member (M3) connected to the output element (FR) of the speed increasing planetary mechanism (G1), the first member (M1) and the second The first bearing (BG5) disposed between the member (M2) and supporting the load in the direction of the rotation axis (10), and disposed between the first member (M1) and the third member (M3). The second frictional engagement element (C2) for transmitting the output of the second bearing (BG6) for supporting the load in the direction of the rotation axis (10) and the speed increasing planetary mechanism (G2) to the speed changing planetary mechanism (G2). ), And the fourth friction engagement element (C2) is engaged and the output of the speed increasing planetary mechanism (G1) is input to the speed changing planetary mechanism (G2). A thrust force (F1) generated at the output element (FR) of the planetary mechanism (G1); Thrust force generated by the second element of the fast planetary mechanism (G2) (LS) (F2) and is characterized by being set to be the same direction. As one embodiment of the present invention, the output element (FR) is the ring gear (FR) of the speed increasing planetary mechanism (G1), and the second element (LS) is the speed changing planetary mechanism (G2). The ring gear (FR) and the sun gear (LS) may be helical gears whose torsional directions are set so that the thrust forces generated in the same direction are the same.

  In the automatic transmission of the present invention having the speed increasing planetary mechanism, the shift stage where the fourth friction engagement element is engaged and the output of the speed increasing planetary mechanism is input to the speed changing planetary mechanism is It is a step. In such a high speed side shift stage, the output element is an output element so that the thrust force generated by the output element of the speed increasing planetary mechanism and the thrust force generated by the second element of the speed changing planetary mechanism are in the same direction. The ring gear of the speed increasing planetary mechanism and the torsion direction of the sun gear of the speed change planetary mechanism as the second element (the torsion direction of the helical gear) were set. Thereby, in the first member to the third member having high differential rotation at the high speed side gear stage, it is possible to cancel the thrust force generated between the adjacent members, and to reduce the difference. Therefore, the load applied to the first and second bearings arranged between the first member to the third member can be greatly reduced. In this way, it is possible to eliminate or significantly reduce the load on the bearing having the high differential rotation, which is a problem of the speed increasing type multi-stage transmission.

  In addition, since the load on the first and second bearings can be reduced, the first and second bearings can be reduced in size and cost can be reduced by simplifying the configuration. In addition, when thrust needle bearings are used for the first and second bearings, the length of the needle can be shortened by reducing the load-bearing value. Therefore, the diameter of the first and second bearings and the waist of the automatic transmission can be reduced. The size can be reduced. In addition, friction loss due to slippage at the first and second bearings can be reduced, and the power transmission efficiency of the automatic transmission can be improved. Furthermore, in the high-speed side gear stage in which a high-difference rotation occurs between each element by setting the twisting direction that generates the thrust force of the present application, it is arranged not only in the first and second bearings but also in the automatic transmission. The effect of reducing the load applied to the entire internal mechanism including other bearings and cases can also be expected. Therefore, the power transmission efficiency of the automatic transmission can be improved.

  In this automatic transmission, the thrust force (F1) generated by the output element (FR) of the speed increasing planetary mechanism (G1) and the thrust force generated by the second element (LS) of the transmission planetary mechanism (G2). (F2) is in the same direction as the gear position, in addition to the engagement of the fourth friction engagement element (C2), the second friction engagement element (C3) is engaged or the third friction engagement is performed. It may be a gear stage that is achieved by engaging the combination element (B1). According to this, in the high speed type multi-stage transmission, it is possible to reduce the load generated in the first and second bearings at the high-speed side gear stage where the high-difference rotation generated between the elements becomes remarkable, so that the friction loss It is effective in reducing

  In this automatic transmission, the first member (M1), the second member (M2), and the third member (M3) are rotatably supported coaxially with the input shaft (10), and It is desirable that the first bearing (BG5) and the second bearing (BG6) are arranged side by side along the axial direction of the input shaft (10). According to this, the load in the input shaft direction generated between the first to third members can be effectively released by the setting of the torsional direction for generating the thrust force of the present application, and each part including the first and second bearings Can be effectively reduced.

As an embodiment of the automatic transmission, the planetary mechanism for shifting (G2) includes a small-diameter sun gear (SS) that is the first element (LS) and a large diameter that is the second element (LS). It may be a Ravigneaux planetary gear mechanism including pinions (P1, P2) meshing with the sun gear (LS) and a carrier (C) supporting the pinions (P1, P2). By adopting such a Ravigneaux type planetary gear mechanism, it is possible to reduce the size and simplify the configuration of the planetary mechanism for shifting (G2).
In addition, the code | symbol in said parenthesis shows the code | symbol of the component in embodiment mentioned later as an example of this invention.

  According to the present invention, in an automatic transmission having a speed-up planetary mechanism for inputting speed-up rotation to a speed-change planetary mechanism, a load generated on a bearing or the like disposed between parts having a high differential rotation is effectively reduced. Can be reduced.

1 is a skeleton diagram of an automatic transmission according to an embodiment of the present invention. It is a sectional side view which shows the internal structure of an automatic transmission. Fig. 4 is a diagram illustrating each speed stage achieved by the automatic transmission. It is a speed diagram which shows the relationship between the gear stage achieved with an automatic transmission, and the rotation speed ratio of each gear at that time. It is a list of the direction of the thrust load which arises in each gear in each gear stage. It is a graph which shows the comparison of the differential rotation concerning each thrust bearing in each gear stage. It is a table | surface which shows the comparison of the thrust load concerning each bearing in the case where the direction where the twist direction opposite to the case where the twist direction of this invention is applied is applied.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a skeleton diagram showing a power transmission configuration of an automatic transmission according to an embodiment of the present invention. FIG. 2 is a side sectional view showing a specific internal configuration of the automatic transmission. The automatic transmission 1 shown in these drawings outputs a speed-changing rotation with the speed-up planetary mechanism G1 that speeds up and outputs the rotation of the input shaft 10 and the speed-up rotation from the speed-up planetary mechanism G1 as inputs. This is an automatic transmission that includes a speed change planetary mechanism G2 and that achieves a forward speed of 6 forward speeds and 1 speed of reverse speed by these speed increase planetary mechanism G1 and speed change planetary mechanism G2. Here, helical gears are used for the respective gears included in the speed increasing planetary mechanism G1 and the speed changing planetary mechanism G2. In the following description, the axial direction refers to the axial direction of the input shaft 10, and the left to right refers to the left and right on the drawing in FIG. 1 or FIG.

  The speed increasing planetary mechanism G1 has a carrier FC as an input element connected to the input shaft 10, and outputs a speed increasing rotation to a ring gear FR as an output element by fixing a sun gear FS as a reaction force element. It is like that. As shown in FIG. 2, the ring gear FR is connected to a third connecting member M3 for transmitting the rotation of the ring gear FR to the speed-change planetary mechanism G2. In the skeleton diagram of FIG. 1, the third connecting member M3 is not shown. The third connecting member M3 is a substantially disk-shaped member that extends from the right end of the ring gear FR to the vicinity of the input shaft 10 in a plane perpendicular to the axial direction, toward the transmission planetary mechanism G2 in the vicinity of the input shaft 10. It extends. The third connecting member M3 is rotatable coaxially with the ring gear FR. Further, the ring gear FR is connected to the carrier C (third element) of the transmission planetary mechanism G2 via a clutch C2 (fourth friction engagement element) connected to the third connecting member M3. By the engagement of the clutch C2, the output of the speed increasing planetary mechanism G1 is input to the speed changing planetary mechanism G2.

  The transmission planetary mechanism G2 is a ravinio type comprising a large-diameter sun gear LS and a small-diameter sun gear SS having different diameters, a long pinion P1 meshing with the large-diameter sun gear LS, and a carrier C supporting a short pinion P2 meshing with the small-diameter sun gear SS. It is composed of a planetary gear mechanism. The long pinion P1 meshes with the large-diameter sun gear LS and meshes with the ring gear R, and the short pinion P2 meshes with the small-diameter sun gear SS. The carrier C is configured such that the rotation of the ring gear FR of the speed increasing planetary mechanism G1 is transmitted via the clutch C2, and can be locked to the case 30 by the brake B2. The ring gear R as an output element for variable speed rotation is connected to the output gear 20.

  The large-diameter sun gear LS is rotatably installed on the same axis as the small-diameter sun gear SS. The large-diameter sun gear LS and the small-diameter sun gear SS function as input elements for non-accelerated rotation (input rotation not via the acceleration planetary mechanism G1) in the transmission planetary mechanism G2. The small-diameter sun gear SS is connected to the clutch C1 (first friction engagement element) via the first connecting member M1. The first connecting member M1 is formed of a substantially cylindrical member disposed on the outer periphery of the input shaft 10 so that the rotation of the input shaft 10 is transmitted via the clutch C1 and rotates coaxially with the input shaft 10. It has become. Therefore, the input from the input shaft 10 is transmitted to the small-diameter sun gear SS via the clutch C1 and the first connecting member M1.

  The large-diameter sun gear LS is connected to the clutch C3 (second friction engagement element) via the second connecting member M2. The second connecting member M2 is a substantially cylindrical member installed on the outer periphery of the first connecting member M1, and the rotation of the input shaft 10 is transmitted via the clutch C3, so that the input shaft 10 and the first connecting member M2 are transmitted. And rotate on the same axis. Therefore, the input from the input shaft 10 is transmitted to the large-diameter sun gear LS via the clutch C3 and the second connecting member M2. The large-diameter sun gear LS and the second connecting member M2 are fixed to the case (fixed side member) 30 of the automatic transmission 1 by a brake B1 (third friction engagement element).

  As shown in FIG. 2, the third connecting member M3, the first connecting member M1 and the small-diameter sun gear SS, and the second connecting member M2 and the large-diameter sun gear LS are arranged in this order from the side near the speed increasing planetary mechanism G1. Are adjacently arranged along the axial direction of the input shaft 10.

  In the automatic transmission 1, a plurality of thrust bearings are disposed between the gears and members adjacent in the axial direction. As such thrust bearings, there are bearings BG2 to BG8 shown in FIGS. The bearing BG2 is a bearing that supports the member 21 that connects the input shaft 10 and the clutch C1, and is disposed in a gap in the axial direction between the member 21 and the case 30. The bearing BG3 is a bearing that supports the member 22 that connects the clutch C1 and the first coupling member M1. Further, the bearing BG4 is disposed in the gap between the second connecting member M2 and the member 22. A load applied to the large-diameter sun gear LS and the second connecting member M2 is supported by the bearing BG4.

  The bearing BG5 (first bearing) is disposed between the right end of the small diameter sun gear SS and the left end of the large diameter sun gear LS. The small-diameter sun gear SS (first connecting member M1) and the large-diameter sun gear LS (second connecting member M2) disposed adjacent to each other are supported by the bearing BG5 so as to be relatively rotatable. The bearing BG6 is disposed between the right end of the third connecting member M3 and the left end of the small-diameter sun gear SS (first connecting member M1). The first connecting member M1 and the third connecting member M3 that are adjacently disposed in the axial direction are supported by the bearing BG6 so as to be relatively rotatable.

  The bearing BG7 supports the left side of the third connecting member M3. The bearing BG8 supports the right side of the sun gear FS of the speed increasing planetary mechanism G1. Further, the bearing BG1 shown in FIGS. 1 and 2 is a bearing that supports the output gear 20 from its inner peripheral side and supports a radial load generated in the output gear 20.

  In the automatic transmission 1 having the above-described configuration, a shift stage corresponding to the range selected by the driver is achieved by control by a control mechanism (not shown). FIG. 3 is a diagram illustrating each gear stage achieved in the automatic transmission 1 by engagement of the clutches C1 to C3 and the brakes B1 and B2. FIG. 4 is a speed diagram showing the relationship between the shift speeds (first speed to sixth speed and reverse speed) achieved in the automatic transmission 1 and the rotation speed ratio of each shift element at that time. It is. In the automatic transmission 1, each gear stage is achieved by engagement and disengagement of the clutches C1 to C3 and the brakes B1 and B2 shown in FIG. 3 (◯ indicates engagement and no symbol indicates release). Hereinafter, each shift stage will be described in order.

  The first speed (1st) is achieved by engagement of the clutch C1 and the brake B2. In this case, in the shifting planetary mechanism G2, only non-accelerated rotation from the input shaft 10 via the clutch C1 is input to the small-diameter sun gear SS. Then, a reaction force is applied to the carrier C locked by the engagement of the brake B2, and the rotation of the ring gear R is output to the output gear 20. The rotation of the ring gear R here is a reduced rotation of the maximum reduction ratio. Note that at the first speed, the clutch C2 is not engaged, and therefore, there is no input of speed-up rotation from the speed-up planetary mechanism G1 to the speed-change planetary mechanism G2.

  The second speed (2nd) is achieved by engagement of the clutch C1 and the brake B1. In this case, in the shifting planetary mechanism G2, only non-accelerated rotation from the input shaft 10 via the clutch C1 is input to the small-diameter sun gear SS. Then, a reaction force is applied to the large-diameter sun gear LS locked by the engagement of the brake B1, and the reduced rotation of the ring gear R is output to the output gear 20. The reduction ratio at this time is smaller than that of the first gear. Even at the second speed, since the clutch C2 is not engaged, there is no input of the speed increasing rotation from the speed increasing planetary mechanism G1 to the speed changing planetary mechanism G2.

  The third speed (3rd) is achieved by simultaneous engagement of the clutch C1 and the clutch C3. In this case, the non-accelerated rotation of the input shaft 10 is simultaneously input to the small-diameter sun gear SS and the large-diameter sun gear LS of the speed-change planetary mechanism G2 via the clutch C1 and the clutch C3, and the speed-change planetary mechanism G2 is directly connected. Therefore, the rotation of the ring gear R, which is the same rotation as the input rotation to the small diameter sun gear SS and the large diameter sun gear LS, is output to the output gear 20. The rotation of the ring gear R is the same as the rotation of the input shaft 10. Even at the third speed, since the clutch C2 is not engaged, there is no input of the speed increasing rotation from the speed increasing planetary mechanism G1 to the speed changing planetary mechanism G2.

  The fourth speed (4th) is achieved by simultaneous engagement of the clutch C1 and the clutch C2. In this case, the speed increasing rotation that has passed through the speed increasing planetary mechanism G1 from the input shaft 10 is input to the carrier C of the speed changing planetary mechanism G2 via the clutch C2, and non-increasing input from the input shaft 10 via the clutch C1. High speed rotation is input to the small-diameter sun gear SS. Therefore, an intermediate rotation between these two inputs is output to the output gear 20 as the rotation of the ring gear R. The rotation of the ring gear R is a rotation slightly increased with respect to the rotation of the input shaft 10.

  The fifth speed (5th) is achieved by simultaneous engagement of the clutch C2 and the clutch C3. In this case, the speed increasing rotation that has passed through the speed increasing planetary mechanism G1 from the input shaft 10 is input to the carrier C of the speed changing planetary mechanism G2 via the clutch C2, and non-increasing input from the input shaft 10 via the clutch C3. High speed rotation is input to the large-diameter sun gear LS. The rotation corresponding to these two inputs is output to the output gear 20 as the rotation of the ring gear R. The rotation of the ring gear R is a rotation increased with respect to the rotation of the input shaft 10.

  The sixth speed (6th) is achieved by engagement of the clutch C2 and the brake B1. In this case, the speed increasing rotation that has passed through the speed increasing planetary mechanism G1 is input from the input shaft 10 to the carrier C of the speed changing planetary mechanism G2 via the clutch C2. Then, a reaction force is applied to the large-diameter sun gear LS locked by the engagement of the brake B 1, and the further accelerated rotation of the ring gear R is output to the output gear 20.

  The reverse speed (Rvs) is achieved by engagement of the clutch C3 and the brake B2. In this case, non-accelerated rotation via the clutch C3 from the input shaft 10 is input only to the large-diameter sun gear LS of the shifting planetary mechanism G2, and a reaction force is applied to the carrier C locked by the engagement of the brake B2. The reverse rotation of the ring gear R is transmitted to the output gear 20. Even in the reverse speed, since the clutch C2 is not engaged, there is no input of the speed increasing rotation from the speed increasing planetary mechanism G1 to the speed changing planetary mechanism G2.

  FIG. 5 shows the thrust loads generated in the gears of the sun gear FS and the ring gear FR of the speed increasing planetary mechanism G1 and the small diameter sun gear SS, the large diameter sun gear LS, and the ring gear R of the speed changing planetary mechanism G2. It is a table | surface which shows the list of directions. In the figure, the direction of the thrust load generated in the output gear 20 and a driven gear (not shown) connected thereto is also shown. As shown in the figure, when the sun gear FS and the ring gear FR of the speed increasing planetary mechanism G1 are rotated by receiving an input from the input shaft 10, their torsional forces are generated in opposite directions. The direction (which indicates the twisting direction of the teeth with respect to the rotation direction of the helical gear, the same applies hereinafter) is set. As a result, the thrust force generated by the sun gear FS and the ring gear FR is offset inside the speed increasing planetary mechanism G1.

  In the automatic transmission 1, the speed-up rotation that has passed through the speed-up planetary mechanism G1 from the input shaft 10 is input to the speed-change planetary mechanism G2. The fourth speed stage in which the clutch C2 is engaged, Each of the fifth speed and the sixth speed, that is, the higher speed gear. Then, in the fourth, fifth and sixth speeds at which the speed increasing rotation is input to the speed changing planetary mechanism G2, the thrust force F1 generated in the ring gear FR of the speed increasing planetary mechanism G1, and the speed changing planetary mechanism G2 The twisting directions of the ring gear FR and the large-diameter sun gear LS are set so that the thrust force F2 generated in the large-diameter sun gear LS is in the same direction (here, leftward).

  More specifically, the thrust force F1 generated by the ring gear FR of the speed increasing planetary mechanism G1 and the thrust force F2 generated by the large-diameter sun gear LS of the speed changing planetary mechanism G2 are in the same direction. Of the fourth, fifth, and sixth gear speeds that are input from the planetary mechanism G1 to the shifting planetary mechanism G2, the rotation of the input shaft 10 is transmitted to the large-diameter sun gear LS of the shifting planetary mechanism G2 by engaging the clutch C3. Or the sixth speed in which the large-diameter sun gear LS is fixed to the case 30 by the engagement of the brake B2.

  Referring to the direction of the thrust force shown in FIG. 5, in the automatic transmission 1 of the present embodiment, the thrust force generated in the large-diameter sun gear LS of the speed planetary mechanism G2 at the fifth and sixth speeds is the load on the bearing BR5. Acts as Further, the thrust force generated in the small-diameter sun gear SS of the shifting planetary mechanism G2 at the first to fourth speeds, and the thrust force generated in the large-diameter sun gear LS of the shifting planetary mechanism G2 at the fifth and sixth speeds. Acts as a load on the bearing BR6.

  FIG. 6 is a graph showing a comparison of differential rotations applied to the bearings BG2 to BG8 at the first speed to the sixth speed. Further, FIG. 7 shows the fifth in the case where the combination of torsional directions according to the present invention (the torsional direction of each gear generating the thrust load in FIG. 5) is applied and in the case where the opposite combination of torsional directions is applied. It is a table | surface which shows the comparison of the thrust load concerning the bearing BG4 and the bearing BG5 in a speed stage and a 6th speed stage. In FIG. 7, the thrust loads of the bearing BG4 and the bearing BG5 are represented by relative values where the thrust load applied to the bearing BG5 at the sixth speed is 1.

  In the automatic transmission 1 of this embodiment provided with the speed increasing planetary mechanism G1 for inputting speed increasing rotation to the speed changing planetary mechanism G2, as shown in FIG. 6, differential rotation generated in the bearings BG2 to BG8 (bearing BG2 to BG2). Comparing the rotation difference of the members arranged on both sides of each BG8), the differential rotation generated in the bearings BG4, BG5, and BG6 at the fifth and sixth speeds, which are the high speed gears, becomes relatively remarkable. ing. In particular, at the sixth speed, all the differential rotations generated in the bearings BG4, BG5, and BG6 are maximized. Therefore, from the viewpoint of effectively reducing the internal load of the automatic transmission 1, the thrust load applied to the bearings BG4, BG5, and BG6 that cause high-difference rotation at the fifth speed and the sixth speed is as much as possible. It is effective to reduce it.

  Therefore, by applying the twist direction of the present invention, the thrust force F1 generated in the ring gear FR of the speed increasing planetary mechanism G1 at the fifth speed and the sixth speed and the large-diameter sun gear of the speed changing planetary mechanism G2. If the thrust force F2 generated in the LS is set to be in the same direction, the bearings BG4, BG5, BG6 at the fifth speed stage and the sixth speed stage as compared with the case where the opposite twist direction is applied. (In particular, the thrust load applied to the bearings BG4, BG5) can be greatly reduced (see FIG. 7). That is, reducing the thrust force generated between the first connecting member M1 and the second connecting member M2 having high differential rotation at the high speed side gear stage, between the first connecting member M1 and the third connecting member M3, and the like. Can do. Thereby, the load concerning each bearing BG4, BG5, BG6 arrange | positioned among these 1st connection member M1, 2nd connection member M2, and 3rd connection member M3 can be reduced effectively. Therefore, it is possible to greatly reduce the load on the bearing having the high differential rotation, which is a problem of the speed increasing type automatic transmission 1 as in the present embodiment.

  In addition, the bearings BG4, BG5, and BG6 can be reduced in size and cost can be reduced by simplifying the configuration. In particular, when a thrust needle bearing is used for the bearings BG4, BG5, and BG6, the length of the needle can be shortened by reducing the load-bearing value. The size can be reduced. Further, it is possible to reduce friction loss due to slippage at the bearings BG4, BG5, and BG6, and the power transmission efficiency by the automatic transmission 1 can be improved.

  Furthermore, according to the setting of the torsion direction of the gear that generates the thrust force of the present application, the first connecting member M1, the second connecting member M2, and the third connecting member M3, which cause high differential rotation at the high speed side gear, In addition to the bearings BG4, BG5, and BG6 that are directly supported, an effect of reducing the overall load of the internal mechanism including the other bearings and the case 30 disposed in the automatic transmission 1 can be expected. Therefore, the energy loss inside the automatic transmission 1 can be effectively reduced, and the power transmission efficiency can be improved.

  As described above, according to the automatic transmission 1 of the present embodiment, the thrust force F1 generated by the ring gear FR and the thrust force F2 generated by the large-diameter sun gear LS are in the same direction at the high speed side gear. With this setting, the load applied to the bearings BG4, BG5, BG6 and the like supporting the first connecting member M1, the second connecting member M2, and the third connecting member M3 having high differential rotation can be released in the axial direction. it can. Therefore, the load applied to the bearings BG4, BG5, BG6 and the like at the high speed side gear can be greatly reduced.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. For example, as long as the automatic transmission according to the present invention is an automatic transmission that includes a speed-up planetary mechanism for inputting speed-up rotation to the speed-change planetary mechanism, the specific configuration is not necessarily limited to the above-described embodiment. It is not limited to what is shown. Therefore, as long as it is within the range having the configuration requirements of the present application, other configurations may be appropriately adopted as the specific configuration such as the number of gears and the arrangement of the gears included in the speed increasing planetary mechanism or the speed changing planetary mechanism. Is possible.

1 Automatic transmission 10 Input shaft 20 Output gear 30 Case (fixed side member)
B1 brake (third friction engagement element)
B2 Brake BG2 to BG8 Bearing (Thrust bearing)
C1 clutch (first friction engagement element)
C2 clutch (fourth friction engagement element)
C3 clutch (second friction engagement element)
G1 Speed increase planetary mechanism G2 Speed change planetary mechanism SS Small-diameter sun gear (first element)
LS large-diameter sun gear (second element)
M1 first connecting member (first member)
M2 second connecting member (second member)
M3 third connecting member (third member)
P1 Long pinion P2 Short pinion C Carrier (third element)
R ring gear FC carrier (input element)
FR ring gear (output element)
FS sun gear (reaction force element)

Claims (5)

A speed increasing planetary mechanism that receives an input to an input element connected to an input shaft and outputs a speed increasing rotation to an output element by fixing a reaction force element;
In an automatic transmission that achieves a multi-stage shift by a speed change planetary mechanism that outputs a speed change rotation with the speed increase rotation from the speed increase planetary mechanism as an input,
A first member for transmitting an input from the input shaft to the first element of the speed-change planetary mechanism via the first friction engagement element;
A second member for transmitting an input from the input shaft to a second element of the transmission planetary mechanism via a second friction engagement element;
A third friction engagement element for fixing the second member to the fixed side member;
A third member connected to the output element of the speed increasing planetary mechanism;
A first bearing disposed between the first member and the second member and supporting a load in the rotational axis direction; and disposed between the first member and the third member in the rotational axis direction. A second bearing supporting the load of
A fourth friction engagement element for transmitting the output of the speed increasing planetary mechanism to the speed changing planetary mechanism;
With
Thrust force generated at the output element of the speed increasing planetary mechanism when the fourth friction engagement element is engaged and the output of the speed increasing planetary mechanism is at the shift speed input to the speed changing planetary mechanism. And the thrust force generated by the second element of the transmission planetary mechanism is set to be in the same direction. A shift stage in which the thrust force generated by the output element of the speed increasing planetary mechanism and the thrust force generated by the second element of the transmission planetary mechanism are in the same direction,
In addition to the engagement of the fourth friction engagement element, the shift stage is achieved by the engagement of the second friction engagement element or the engagement of the third friction engagement element. The automatic transmission according to claim 1. The output element is a ring gear of the speed increasing planetary mechanism, and the second element is a sun gear of the speed changing planetary mechanism,
3. The automatic transmission according to claim 1, wherein the ring gear and the sun gear are helical gears whose torsional directions are set so that thrust forces generated in the same direction are the same. . The first member, the second member, and the third member are rotatably supported on the same axis as the input shaft, and the shaft of the input shaft is sandwiched between the first bearing and the second bearing. The automatic transmission according to claim 1, wherein the automatic transmission is arranged in a direction. The transmission planetary mechanism is a Ravigneaux planetary gear mechanism including a pinion that meshes with a small-diameter sun gear that is the first element and a large-diameter sun gear that is the second element, and a carrier that supports the pinion. The automatic transmission according to any one of claims 1 to 4, wherein:

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