JP2015059578A - Automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission which can suppress a length of the automatic transmission in an axial line direction, is reducible in size, and forms a forward 9-speed gear stage and a reverse 1-speed gear stage.SOLUTION: An automatic transmission comprises: a first double-row planetary gear having integrated first and second pinions, a common carrier which rotatably and pivotally supports a sub-pinion engaged with the first pinion, a first sun gear engaged with the first pinion, and fixed to a housing, a common ring gear engaged with the sub-pinion, and a second sun gear engaged with the second pinon; a second double-row planetary gear having third and fourth sun gears, third and fourth ring gears, and third and fourth carriers; first to fourth clutches; and first and second brakes.

Description

  The present invention relates to an automatic transmission capable of forming nine forward speeds and one reverse speed using a first double-row planetary gear and a second double-row planetary gear, four clutches, and two brakes.

  It has four planetary gears, four clutches, and two brakes, and engages two engagement elements of the four clutches and the two brakes to form a forward 9-speed and a reverse 1-speed gear stage. An automatic transmission is described in Patent Document 1.

  It also has four planetary gears, two clutches, and four brakes, and engages two engagement elements of the two clutches and the four brakes so that the forward 9-speed and the reverse 1-speed gear stages are obtained. An automatic transmission to be formed is described in Patent Document 2.

U.S. Pat. No. 7,226,381 US Pat. No. 7,364,527

  The one described in Patent Document 1 or Patent Document 2 connects the first-row planetary gear 20 and the second-row planetary gear 30 via a connecting member 70, so that the axial length of the automatic transmission is long. As the size of the automatic transmission increases, the weight of the automatic transmission increases and the cost increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic transmission that can suppress the axial length of the automatic transmission and can be miniaturized.

  According to a first aspect of the present invention, there is provided a housing, an input shaft that is rotatably supported by the housing about a rotation axis, a first pinion, a second pinion, a sub-pinion that meshes with the first pinion, and the sub-pinion A common carrier that rotatably supports a pinion, a first sun gear that meshes with the first pinion and is fixed to the housing, a common ring gear that meshes with the sub-pinion, and a second sun gear that meshes with the second pinion The first double-row planetary gear, the third sun gear, the third ring gear, the third sun gear, and the third ring gear that are supported on the housing coaxially with the rotation axis and coupled to the input shaft. A third pinion that meshes, a third carrier that rotatably supports the third pinion, a fourth sun gear coupled to the third sun gear, and the third pinion A fourth ring gear coupled to the carrier, a fourth pinion that meshes with the fourth sun gear and the fourth ring gear, and a fourth carrier that rotatably supports the fourth pinion, and the rotation to the housing A second double-row planetary gear supported coaxially with the axis, an output shaft supported rotatably around the rotational axis on the housing and coupled to the fourth carrier, and the third and third coupled to the input shaft. A first clutch for releasably connecting a fourth sun gear; a second clutch for releasably connecting the third carrier and the fourth ring gear connected to the input shaft; and the common ring gear; A third clutch for releasably connecting the third ring gear; a fourth clutch for releasably connecting the second sun gear and the third ring gear; 3 a first brake for detachably securing the ring gear to the housing, is to include a second brake for detachably fixing the third carrier and the fourth ring gear are connected to each other in said housing.

  According to the first aspect, the first double-row planetary gear meshes with the first and second pinions and the sub-pinion that meshes with the first pinion, and the common carrier that rotatably supports the first pinion and is fixed to the housing. The first sun gear, the common ring gear that meshes with the sub-pinion, and the second sun gear that meshes with the second pinion are compared to the conventional automatic transmission in which two rows of planetary gears are connected in parallel. The length of the automatic transmission in the axial direction can be suppressed, and the automatic transmission can be downsized.

  In addition, since the second row of the first double-row planetary gear is not a planetary gear but only a reverse gear is constituted by the second sun gear and the second pinion, the gear ratio between the second sun gear and the second pinion is increased. As a result, the degree of freedom of the gear can be increased as compared with the Ravigneaux type double-row planetary gear, and the interval between the respective gears can be set appropriately.

  According to a second aspect of the present invention, there is provided a housing, an input shaft that is rotatably supported by the housing around a rotation axis, a long pinion and a second pinion that mesh with each other, and the long pinion and the second pinion that rotate. A common carrier that is supported, a first sun gear that is coupled to the input shaft and meshes with the long pinion, a second sun gear that meshes with the second pinion, and a common that meshes with the long pinion and is fixed to the housing A first Ravigneaux type double-row planetary gear supported on the housing coaxially with the rotation axis, a third sun gear, a third ring gear, a third sun gear, and a third ring gear. A third pinion, a third carrier rotatably supporting the third pinion, and the third sun gear. A fourth sun gear; a fourth ring gear coupled to the third carrier; a fourth pinion that meshes with the fourth sun gear and the fourth ring gear; and a fourth carrier that rotatably supports the fourth pinion. A second double-row planetary gear supported on the housing coaxially with the rotation axis; an output shaft supported on the housing so as to be rotatable about the rotation axis; and connected to the fourth carrier; and the input shaft; A first clutch that removably connects the third and fourth sun gears connected to each other, and a third clutch and fourth ring gear that are connected to the input shaft and connected to each other. A second clutch, a third clutch for releasably connecting the common carrier and the third ring gear, and a second sun gear and the third ring gear for releasable connection. A fourth clutch, a first brake for releasably fixing the third ring gear to the housing, and a second brake for releasably fixing the third carrier and the fourth ring gear connected to each other to the housing. And providing a brake.

  According to the invention according to claim 2 described above, the first double-row planetary gear is constituted by a Ravigneaux type having a common pinion and ring gear, so that the length of the automatic transmission in the axial direction can be suppressed, and the automatic transmission The machine can be downsized.

It is a figure for demonstrating the automatic transmission which concerns on the 1st Embodiment of this invention. It is a figure which shows the operating state of the clutch and brake in each gear stage which concerns on 1st Embodiment. It is a speed diagram which shows the rotation ratio of each element of the planetary gear in each gear stage which concerns on 1st Embodiment. It is a figure for demonstrating the automatic transmission which concerns on the 2nd Embodiment of this invention. It is a figure which shows the operating state of the clutch and brake in each gear stage which concerns on 2nd Embodiment. It is a speed diagram which shows the rotation ratio of each element of the planetary gear in each gear stage which concerns on 2nd Embodiment.

  Hereinafter, a first embodiment of an automatic transmission according to the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 10 denotes an automatic transmission according to the present invention, which, for example, shifts the rotation of an input shaft 12 rotated by an engine 11 of an automobile and transmits it to an output shaft 13. The input shaft 12 and the output shaft 13 are supported by a substantially cylindrical housing (for example, a transmission case) 15 that is fixed to a vehicle body so as to be rotatable around a rotation axis O1.

  The automatic transmission 10 includes first and second double-row planetary gears 21 and 22, four clutches C1 to C4, and two brakes B1 and B2. The first and second double-row planetary gears 21 and 22 are arranged in the housing 15 in the direction of the rotation axis of the input shaft 12. Then, two of the six engaging elements (C1 to C4, B1, B2) are engaged to form a forward 9th speed and a reverse 1st gear. The automatic transmission 10 is configured substantially symmetrically with respect to the rotation axis O1, but the lower half is omitted in FIG.

In FIG. 1, the first double-row planetary gear 21 is supported by a housing 15 on a concentric shaft with the input shaft 12. The first double-row planetary gear 21 includes integrally formed first and second pinions P1, P2, a sub-pinion P5 that meshes with the first pinion P1, and a common carrier CA1 that rotatably supports the sub-pinion P5. The first sun gear S1 meshed with the first pinion P1 and fixed to the housing 15, the common ring gear R1 meshed with the sub-pinion P5, and the second sun gear S2 meshed with the second pinion P2. The common carrier CA1 is integrally connected (directly connected) to the input shaft 12 via the connecting shaft 31. The connecting shaft 31 includes a horizontal shaft portion 31a connected to the common carrier CA1, a vertical wall portion 31b extending radially from one end of the horizontal shaft portion 31 on the input shaft 12 side toward the inner periphery of the housing 15, A large-diameter horizontal shaft portion 31c extending horizontally from the tip of the vertical wall portion 31b toward the input shaft 12, and a radial shaft extending from one end of the horizontal shaft portion 31c toward the rotation axis O1 12, a vertical wall portion 31 d connected to 12.
And the outer periphery of the 1st and 2nd clutches C1 and C2 is being fixed to the inner periphery of the horizontal shaft part 31c. As a result, the first and second clutches C1 and C2 can be arranged at positions separated from the rotation axis O1, so that the diameter (friction engagement area) of the friction engagement portions of the first and second clutches C1 and C2 can be increased. The torque capacity of the first and second clutches C1 and C2 can be increased.

  Thus, when the first and second pinions P1, P2 are rotated by the input shaft 12, the common ring gear R1 is in the same direction as the rotation direction of the input shaft 12 according to the gear ratio between the first sun gear S1 and the common ring gear R1. And the second sun gear S2 is decelerated and rotated in the direction opposite to the rotation direction of the input shaft 12.

  The common ring gear R1 is detachably coupled to the third ring gear R3 of the second double-row planetary gear 22 via the coupling member 34 by the third clutch C3. The connecting member 34 is detachably connected to the second sun gear S2 by the fourth clutch C4. The outer periphery of the fourth clutch C4 is connected to the connecting member 34. At this time, the diameter of the friction engagement portion of the fourth clutch C4 can be increased by arranging the horizontal shaft portion of the connecting member 34 to which the fourth clutch C4 is connected at a position separated from the rotational axis O1, and the fourth clutch The torque capacity of C4 can be increased.

  The second double-row planetary gear 22 includes third and fourth planetary gears 22a and 22b. The third and fourth planetary gears 22 a and 22 b are supported on the housing 15 coaxially with the input shaft 12. The third and fourth planetary gears 22a and 22b are juxtaposed in the axial direction.

  The third sun gear S3 of the third planetary gear 22a and the fourth sun gear S4 of the fourth planetary gear 22b are connected to each other via a connecting shaft 35. The connecting shaft 35 has a horizontal shaft portion 35 a that is disposed concentrically with the input shaft 12. One end of the horizontal shaft portion 35a on the input shaft 12 side is connected to a vertical wall portion 35b extending in the radial direction toward the inner periphery of the housing 15, and the vertical wall portion 35b is connected to the above through the first clutch C1. The connecting shaft 31 is connected to the horizontal shaft portion 31c. The third and fourth sun gears S3 and S4 are connected to the other end of the connecting shaft 35 on the output shaft 13 side. Thus, the third and fourth sun gears S3 and S4 are detachably connected to the input shaft 12 by the first clutch C1.

  The third carrier CA3 of the third planetary gear 22a supports the third pinion P3 so as to be rotatable. The third carrier CA3 of the third planetary gear 22a and the fourth ring gear R4 of the fourth planetary gear 22b are connected to each other via a connecting member 36. The connecting member 36 is integrally connected to the connecting shaft 37. The connecting shaft 37 has a horizontal shaft portion 37 a disposed on the concentric shaft between the connecting shaft 31 and the connecting shaft 35. One end of the horizontal shaft portion 37a on the input shaft 12 side is connected to a vertical wall portion 37b extending in the radial direction toward the inner periphery of the housing 15, and the vertical wall portion 37b is connected to the above-described portion via the second clutch C1. The connecting shaft 31 is connected to the horizontal shaft portion 31c. The other end of the connecting shaft 37 on the output shaft 13 side is connected to the third carrier CA3 via a vertical wall portion 37c extending radially toward the inner periphery of the housing 15. Accordingly, the third carrier CA3 and the fourth ring gear R4 are detachably coupled to the input shaft 12 by the first clutch C2.

  The third sun gear S3 and the fourth sun gear S4 connected to each other are detachably connected to the input shaft 12 by the first clutch C1. The third carrier CA3 and the fourth ring gear R4 that are connected to each other are detachably connected to the input shaft 12 by the second clutch C2.

  The third ring gear R3 is detachably fixed to the housing 15 by the first brake B1 fixed to the inner peripheral portion of the housing 15, and the rotation is restricted. Further, the fourth ring gear R4 and the third carrier connected to each other are removably fixed to the housing 15 by the second brake B2 fixed to the inner peripheral portion of the housing 15, and the rotation is restricted. The fourth pinion P4 is rotatably supported by the fourth planetary gear 22b. The fourth carrier CA4 of the fourth planetary gear 22b is integrally connected to the output shaft 13 via the connecting member 38. The output shaft 13 is coupled to the left and right drive wheels via an output transmission mechanism 17 such as a propeller shaft or a differential gear device.

  The automatic transmission 10 configured as described above is configured to selectively engage the first to fourth clutches C1 to C4 and the first and second brakes B1 and B2, thereby enabling nine forward speeds and one reverse speed. A shift stage can be established. In FIG. 2, when each of the clutches C1 to C4 and the brakes B1 and B2 corresponding to each gear stage is marked with a circle, it indicates that it is in an engaged state.

  When the first to fourth clutches C1 to C4 are selectively engaged and the first and second brakes B1 and B2 are selectively engaged, the speed ratios of the elements of the planetary gears 21 and 22 are as shown in FIG. It becomes like the velocity diagram shown in.

  In the velocity diagram, the elements composed of the sun gear, carrier and ring gear of the first and second double-row planetary gears 21 and 22 are arranged at intervals corresponding to the gear ratio in the horizontal axis direction, and correspond to each element in the vertical axis direction. The speed ratio is taken.

  In the double pinion type first double-row planetary gear 21, the relationship between the rotational speed Ns of the first sun gear S1, the rotational speed Nc of the common carrier CA1, the rotational speed Nr of the common ring gear R1, and the gear ratio λ of the planetary gear is expressed by the formula ( 1).

On the other hand, since the second double-row planetary gear 22 includes third and fourth planetary gears 22a and 22b of a single pinion type, the rotation speed Ns of the sun gear, the rotation speed Nc of the carrier, the rotation speed Nr of the ring gear and the gear ratio of the planetary gear. The relationship with λ is expressed by equation (2). And the gear ratio in each gear stage is calculated based on Formula (1), (2). If the number of teeth of the sun gears S1, S3, S4 is Zs1, Zs3, Zs4 and the number of teeth of the ring gears R1, R3, R4 is Zr1, Zr3, Zr4, the gear ratio of the first double-row planetary gear 21 is λ1 = Zs1 / Zr1 The gear ratios of the third and fourth planetary gears 22a and 22b of the second double-row planetary gear 22 are λ3 = Zs3 / Zr3 and λ4 = Zs4 / Zr4, respectively.
Nr = (1-λ) Nc + λNs (1)
Nr = (1 + λ) Nc−λNs (2)

  In the first double-row planetary gear 21, the distance between the vertical line of the common carrier CA1 and the vertical line of the first sun gear S1 is regarded as 1, and the vertical line of the common ring gear R1 is changed from the horizontal line of the first carrier CA1 to the first sun gear S1. Are arranged on the same side as the vertical line by a distance λ1. In addition, the vertical line of the second sun gear S2 that constitutes the reverse gear with the second pinion P2 extends from the vertical line of the fixed sun gear S1 to the side opposite to the vertical line of the common ring gear R1 (reverse side). And the second pinion P2.

  For the single pinion type third planetary gear 22a of the second double-row planetary gear 22, the distance between the vertical line of the third sun gear S3 and the vertical line of the third carrier CA3 is regarded as 1, and the vertical line of the third ring gear R3 is the first line. The third carrier CA3 is arranged on the opposite side of the vertical line of the third sun gear S3 from the vertical line by a distance λ3.

  Similarly, for the single pinion type fourth planetary gear 22b of the second double-row planetary gear 22, the distance between the vertical line of the fourth sun gear S4 and the vertical line of the fourth carrier CA4 is regarded as 1, and the fourth ring gear R4 The vertical line is arranged apart from the vertical line of the fourth carrier CA4 by a distance λ4 on the opposite side of the vertical line of the fourth sun gear S3. At this time, since the fourth sun gear S4 is integrally connected to the third sun gear S3, and the fourth ring gear R4 is integrally connected to the third carrier CA3, the vertical directions of the fourth sun gear S4 and the fourth ring gear R4 are The lines are common to the vertical lines of the third sun gear S3 and the third carrier CA3.

  In the speed diagram, C1 to C4, B1, and B2 are written at points where the first to fourth clutches C1 to C4 and the first and second brakes B1 and B2 are selectively operated.

  In the velocity diagram created in this way, the elements corresponding to the four vertical lines are defined as the first, second, third, and fourth elements in the order of the vertical lines. In the embodiment, the third ring gear R3 as the first element is connected in parallel to the third and fourth clutches C3 and C4 and the first brake B1, and is connected to each other as the second element. CA3 and the fourth ring gear R4 are connected in parallel to the second clutch C2 and the second brake B2, and the fourth carrier CA4 as the third element is connected to the output shaft 13 and connected to each other as the fourth element. The third and fourth sun gears S3 and S4 are connected to the first clutch C1.

  Next, the operation of each gear stage will be described. In the case of the first forward speed, the fourth clutch C4 and the second brake B2 are engaged. The engagement of the fourth clutch C4 connects the second sun gear S2 to the third ring gear R3, and the engagement of the second brake B2 restricts the rotation of the fourth ring gear R4 and the third carrier CA3 connected to each other. .

  Thereby, the second sun gear S2 is reversely rotated by the rotation of the common carrier CA1 by the input shaft 12, and is transmitted to the third ring gear R3. Accordingly, the third and fourth sun gears S3 and S4 connected to each other are rotated at a rotation speed determined by the rotation speed of the third ring gear R3 and the gear ratio of the third ring gear R3 and the third sun gear S3. The fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth sun gear S4 and the gear ratio between the fourth ring gear R4 and the fourth sun gear S4. As a result, the output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the first gear.

  In the case of the second forward speed, the first clutch C1 and the second brake B2 are engaged. The third and fourth sun gears S3, S4 connected to each other are connected to the input shaft 12 by the engagement of the first clutch C1, and the fourth ring gear R4 and the third third gear connected to each other by the engagement of the second brake B2. Carrier CA3 is restricted from rotating.

  As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth sun gear S4 and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4, and is thus coupled to the fourth carrier CA4. The output shaft 13 is driven to rotate forward at the gear ratio of the second speed gear.

  In the case of the third forward speed, the first clutch C1 and the fourth clutch C4 are engaged. The third and fourth sun gears S3 and S4 connected to each other are connected to the input shaft 12 by the engagement of the first clutch C1, and the second sun gear S2 is connected to the third ring gear R3 by the engagement of the fourth clutch C4. Is done.

  As a result, the rotation of the common carrier CA1 by the input shaft 12 causes the third ring gear R3 to rotate in the same manner as described in the first forward speed, so that the third carrier CA3 and the fourth ring gear R4 are connected to the third ring gear R3. And the third sun gear S3 and the gear ratio between the third ring gear R3 and the third sun gear S3. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the third speed gear.

  In the case of the fourth forward speed, the first clutch C1 and the first brake B1 are engaged. The third and fourth sun gears S3 and S4 connected to each other are connected to the input shaft 12 by the engagement of the first clutch C1, and the rotation of the third ring gear R3 is restricted by the engagement of the first brake B1.

  Thereby, the third carrier CA3 and the fourth ring gear R4 are rotated at a rotation speed determined by the rotation speed of the third sun gear S3 and the gear ratio of the third ring gear R3 and the third sun gear S3. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the fourth speed gear.

  In the case of the fifth forward speed, the first clutch C1 and the third clutch C3 are engaged. The third and fourth sun gears S3 and S4 connected to each other are connected to the input shaft 12 by the engagement of the first clutch C1, and the common ring gear R1 is connected to the third ring gear R3 by the engagement of the third clutch C3. The

  Thereby, the rotation of the common carrier CA1 by the input shaft 12 causes the common ring gear R1 and the third ring gear R3 to rotate at a rotation speed determined by the rotation speed of the common carrier CA1 and the gear ratio of the common ring gear R1 and the sun gear S1. Is done. Accordingly, the third carrier CA3 and the fourth ring gear R4 are determined by the rotational speed of the third ring gear R3, the rotational speed of the third sun gear S3, and the gear ratio of the third ring gear R3 and the third sun gear S3. It is rotated by. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the fifth gear.

  In the case of the sixth forward speed, the first and second clutches C1 and C2 are engaged. The third and fourth sun gears S3 and S4 are connected to the input shaft 12 by the engagement of the first clutch C1, and the third carrier CA3 and the fourth ring gear R4 are connected to the input shaft 12 by the engagement of the second clutch C2. Is done.

  Thereby, the rotation of the input shaft 12 is transmitted to the third and fourth sun gears S3 and S4 through the first clutch C1, and at the same time, to the third carrier CA3 and the fourth ring gear R4 through the second clutch C2. Communicated. As a result, the fourth carrier CA4 connected to the output shaft 13 is rotated integrally with the input shaft 12, and the output shaft 13 is driven to rotate in the forward direction at a gear ratio of the sixth speed.

  In the case of the seventh forward speed, the second and third clutches C2 and C3 are engaged. The third carrier CA3 and the fourth ring gear R4 are coupled to the input shaft 12 by the engagement of the second clutch C2, and the common ring gear R1 is coupled to the third ring gear R3 by the engagement of the third clutch C3.

  As a result, the third carrier CA3 and the fourth ring gear R4 are rotated integrally with the input shaft 12, and the third ring gear R3 is rotated in the same manner as described in the first forward speed. The sun gears S3 and S4 are rotated at a rotation speed determined by the rotation speed of the third carrier CA3, the rotation speed of the third ring gear R3, and the gear ratio of the third ring gear R3 and the third sun gear S3. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the seventh gear.

  In the case of the eighth forward speed, the second clutch C2 and the first brake B1 are engaged. The third carrier CA3 and the fourth ring gear R4 are connected to the input shaft 12 by the engagement of the second clutch C2, and the rotation of the third ring gear R3 is restricted by the engagement of the first brake B1.

  Thus, the third and fourth sun gears S3 and S4 are rotated at a rotation speed determined by the rotation speed of the third carrier CA3 and the gear ratio of the third ring gear R3 and the third sun gear S3. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at the gear ratio of the eighth speed gear.

  In the case of the ninth forward speed, the second clutch C2 and the fourth clutch C4 are engaged. The engagement of the second clutch C2 connects the third carrier CA3 and the fourth ring gear R4 to the input shaft 12, and the engagement of the fourth clutch C4 connects the second sun gear S2 to the third ring gear R3.

  As a result, the rotation of the common carrier CA1 by the input shaft 12 causes the third ring gear R3 to rotate in the same manner as described in the first forward speed, so that the third and fourth sun gears S3 and S4 rotate the third ring gear R3. It is rotated at a rotational speed determined by the speed, the rotational speed of the third carrier CA3, and the gear ratio of the third ring gear R3 and the third sun gear S3. As a result, the fourth carrier CA4 is rotated at a rotational speed determined by the rotational speed of the fourth ring gear R4, the rotational speed of the fourth sun gear S4, and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4. The output shaft 13 connected to the fourth carrier CA4 is driven to rotate forward at a gear ratio of the ninth gear.

  In the case of the first reverse speed, the third clutch C3 and the second brake B2 are engaged. The common ring gear R1 is connected to the third ring gear R3 by the engagement of the third clutch C3, and the rotation of the fourth ring gear R4 and the third carrier CA3 is restricted by the engagement of the second brake B2.

  Accordingly, the third ring gear R3 is rotated at the rotational speed described in the fifth forward speed by the rotation of the common carrier CA1 by the input shaft 12, and therefore the third and fourth sun gears S3 and S4 are connected to the third ring gear R3. The rotation is reversed at a rotation speed determined by the rotation speed and the gear ratio between the third ring gear R3 and the third sun gear S3. Accordingly, the fourth carrier CA4 is reversely rotated at a rotational speed determined by the rotational speed of the fourth sun gear S4 and the gear ratio of the fourth ring gear R4 and the fourth sun gear S4, so that the fourth carrier CA4 is coupled to the fourth carrier CA4. The output shaft 13 is driven in reverse at the gear ratio of the first reverse gear.

  According to the first embodiment described above, the first double-row planetary gear 21 is supported so that the first and second pinions P1, P2 and the first pinion P1 mesh with the first and second pinions P5 and P5. And the first sun gear S1 meshed with the first pinion P1 and fixed to the housing 15, the common ring gear R1 meshed with the sub-pinion P5, and the second sun gear S2 meshed with the second pinion P2. Therefore, compared to the conventional automatic transmission in which two rows of planetary gears are arranged in parallel and connected to each other, the length of the automatic transmission 10 in the axial direction can be suppressed, and the automatic transmission 10 can be downsized. Can be possible.

  In addition, the second row of the first double-row planetary gear 21 is not a planetary gear, but only a reverse gear is constituted by the second sun gear S2 and the second pinion P2, so the second sun gear S2 and the second pinion P2 The gear ratio can be set freely, which can increase the degree of freedom of the gear compared to the normal Ravigneaux type double-row planetary gear, and can set the interval of each gear stage appropriately It becomes.

  Next, a second embodiment of the present invention will be described with reference to FIGS. In the automatic transmission 10 according to the second embodiment, the first double-row planetary gear 21 is constituted by a Ravigneaux type planetary gear having a common pinion and ring gear, and the common ring gear R2 meshing with the pinion is fixed to the housing 15. The third carrier C1 is different from the first embodiment in that the common carrier CA1 is detachably connected to the connecting member 34 connected to the third ring gear R3 by the third clutch C3. Since the other parts are the same as those of the first embodiment, the following mainly describes differences from the first embodiment, and the same reference numerals are used for the same components as those of the first embodiment. The description is omitted.

  As shown in FIG. 4, in the second embodiment, the first double-row planetary gear 121 is constituted by a Ravigneaux type planetary gear having a common pinion P11 and ring gear R2. The first sun gear S <b> 1 of the planetary gear 121 is connected to the input shaft 12 via the connecting member 31. The common ring gear R <b> 2 is fixed to the housing 15 via the connecting member 32.

  The second sun gear S2 is meshed with the long pinion P11 supported by the common carrier CA1 via the auxiliary pinion P12, and is detachably connected to the third ring gear R3 by the fourth clutch C4. Further, the common carrier CA1 is detachably coupled to the third ring gear R3 via the coupling member 32 in parallel with the fourth clutch C4 by the third clutch C3.

  5 and 6 show an engagement table and a velocity diagram in the second embodiment. In FIG. 6, the common ring gear R2 is fixed, the first sun gear S1 is integrally connected to the input shaft 12, and the operating point of the third clutch C3 is on the common carrier CA1. It is different from the one of the form.

  According to the second embodiment described above, since the first double-row planetary gear 121 is configured by the Ravigneaux type in which the pinion P11 and the ring gear R1 are used in common, the automatic operation is the same as described in the first embodiment. The length of the transmission 10 in the axial direction can be suppressed, and the automatic transmission can be downsized.

  In the above-described embodiment, the clutches C1, C2, and C4 can be arranged at positions separated from the rotation axis O1 as much as possible by the configuration of the coupling shafts 31, 35, and 37 and the coupling member 34, so that the torque capacity is reduced. Although an example in which the increase is possible has been described, the present invention is not limited to this.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited to the configurations described in the embodiments, and can take various forms within the scope described in the claims. Is.

DESCRIPTION OF SYMBOLS 10 ... Automatic transmission, 12 ... Input shaft, 13 ... Output shaft, 15 ... Housing, 21 ... 1st double row planetary gear, 22 ... 2nd double row planetary gear, S1-S4 ... Sun gear, CA1, CA3, CA4 ... Carrier, R1-R4: Ring gear, P1-P4: Pinion, P11: Long pinion, P5, P12 ... Sub-pinion, C1-C4 ... Clutch, B1, B2 ... Brake.

Claims (2)

A housing;
An input shaft that is supported on the housing so as to be rotatable around a rotation axis;
A first pinion that meshes with the first pinion and the first pinion, a common carrier that rotatably supports the subpinion, a first sun gear that meshes with the first pinion and is fixed to the housing, A first ring train planetary gear having a common ring gear meshing with the sub-pinion and a second sun gear meshing with the second pinion, supported on the housing coaxially with the rotation axis, and coupled to the input shaft;
A third sun gear, a third ring gear, a third pinion that meshes with the third sun gear and the third ring gear, a third carrier that rotatably supports the third pinion, and the third sun gear are connected. A fourth sun gear; a fourth ring gear coupled to the third carrier; a fourth pinion that meshes with the fourth sun gear and the fourth ring gear; and a fourth carrier that rotatably supports the fourth pinion. A second double-row planetary gear supported on the housing coaxially with the rotational axis;
An output shaft that is rotatably supported around the rotation axis of the housing and connected to the fourth carrier;
A first clutch for releasably connecting the third and fourth sun gears connected to the input shaft;
A second clutch for releasably connecting the third carrier and the fourth ring gear connected to the input shaft;
A third clutch for releasably connecting the common ring gear and the third ring gear;
A fourth clutch for releasably connecting the second sun gear and the third ring gear;
A first brake for releasably fixing the third ring gear to the housing;
A second brake for releasably fixing the third carrier and the fourth ring gear coupled to each other to the housing;
An automatic transmission comprising: A housing;
An input shaft that is supported on the housing so as to be rotatable around a rotation axis;
A long pinion and a second pinion meshing with each other; a common carrier rotatably supporting the long pinion and the second pinion; a first sun gear coupled to the input shaft and meshing with the long pinion; and the second pinion; A Ravigneaux type first double-row planetary gear that has a second sun gear that meshes with, a common ring gear that meshes with the long pinion and is fixed to the housing, and is supported coaxially with the rotational axis in the housing;
A third sun gear, a third ring gear, a third pinion that meshes with the third sun gear and the third ring gear, a third carrier that rotatably supports the third pinion, and the third sun gear are connected. A fourth sun gear; a fourth ring gear coupled to the third carrier; a fourth pinion that meshes with the fourth sun gear and the fourth ring gear; and a fourth carrier that rotatably supports the fourth pinion. A second double-row planetary gear supported on the housing coaxially with the rotational axis;
An output shaft that is rotatably supported around the rotation axis of the housing and connected to the fourth carrier;
A first clutch for releasably connecting the third and fourth sun gears connected to the input shaft;
A second clutch for releasably connecting the third carrier and the fourth ring gear connected to the input shaft;
A third clutch for releasably connecting the common carrier and the third ring gear;
A fourth clutch for releasably connecting the second sun gear and the third ring gear;
A first brake for releasably fixing the third ring gear to the housing;
A second brake for releasably fixing the third carrier and the fourth ring gear coupled to each other to the housing;
An automatic transmission comprising:

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