JP6148632B2 - Automatic transmission - Google Patents

Description

  The present invention relates to an automatic transmission using a planetary gear mechanism.

  In order to improve driving performance and fuel efficiency, automatic transmissions for automobiles are becoming increasingly multi-stage. An automatic transmission generally includes a planetary gear mechanism and an engagement mechanism such as a clutch and a brake, and each gear stage is realized by switching the power transmission path by the engagement mechanism. Patent Document 1 discloses an automatic transmission that achieves 10 forward speeds.

JP 2012-225506 A

  Thus, in an automatic transmission in which the number of forward gears reaches two digits, the λ value (number of sun gear teeth / number of ring gear teeth) of some planetary gear mechanisms can be obtained by setting a general ratio suitable for each gear. There is a case where the pinion gear becomes too small due to the necessity of increasing it. If the pinion gear becomes too small, it will be disadvantageous in terms of assembly and rigidity. It is said that the λ value is generally preferably from 0.3 to 0.7.

  An object of the present invention is to provide an automatic transmission in which the number of forward shift stages can be set to two digits without the λ value of the planetary gear mechanism being too large or too small.

According to the present invention, an input shaft that is rotated by a driving force from a driving source , a plurality of planetary gear mechanisms that include a rotating element including a sun gear, a carrier, and a ring gear, and between the rotating element and the input shaft, or A plurality of engagement mechanisms that can connect any one of the rotating element and the casing, and input from the drive source to the input shaft at a gear ratio according to a combination of engagement and disengagement of the engagement mechanisms. The plurality of planetary gear mechanisms include a first planetary gear mechanism including a first sun gear, a first carrier, and a first ring gear, a second sun gear, and a second carrier. A second planetary gear mechanism having a second ring gear, a third sun gear, a third carrier, a third planetary gear mechanism having a third ring gear, a fourth sun gear, a fourth carrier, and a fourth ring gear having a fourth ring gear. 4 planetary teeth And a third planetary gear mechanism and a fourth planetary gear mechanism, each of which is constituted by connecting two of the rotating elements, and comprising a first to a fourth rotating element. Constituting a gear mechanism, the first carrier and the second ring gear are connected, the first rotating element and the output member are connected, the first ring gear, the second carrier and the second rotating element; And the plurality of engagement mechanisms include a first clutch for detachably connecting the second sun gear and the input shaft, and a first clutch for detachably connecting the first carrier and the input shaft. Two clutches, a third clutch for releasably connecting the third rotating element and the input shaft, a first brake for releasably connecting the first carrier and the casing, and the first sun gear. And the casing can be freely engaged and disengaged A second brake for coupling, a third brake for detachably coupling the third rotating element and the casing, and a fourth brake for detachably coupling the fourth rotating element and the casing. Each shift stage is formed by engaging at least three of the plurality of engagement mechanisms, and the first rotating element is configured by connecting the third ring gear and the fourth carrier, The second rotating element is configured by connecting the third sun gear and the fourth sun gear, the third rotating element is configured by the third carrier, and the fourth rotating element is configured by the fourth ring gear. Ru is, the automatic transmission is provided, characterized in that.

Further, according to the present invention, an input shaft that is rotated by a driving force from a drive source , a plurality of planetary gear mechanisms that include a rotating element composed of a sun gear, a carrier, and a ring gear, and between the rotating element and the input shaft. Or a plurality of engagement mechanisms capable of connecting any of the rotating element and the casing, and the drive source to the input shaft at a gear ratio according to a combination of engagement and disengagement of the engagement mechanisms. In the automatic transmission that outputs the input driving force to the output member, the plurality of planetary gear mechanisms include a first planetary gear mechanism including a first sun gear, a first carrier, and a first ring gear, a second sun gear, 2nd planetary gear mechanism with 2 carriers and 2nd ring gear, 3rd planetary gear mechanism with 3rd sun gear, 3rd carrier and 3rd ring gear, 4th sun gear, 4th carrier and 4th ring gear 4th A star gear mechanism, wherein the third planetary gear mechanism and the fourth planetary gear mechanism are configured by connecting two of the rotating elements, respectively, and include first to fourth rotating elements. Constituting a compound planetary gear mechanism, the first carrier and the second ring gear are connected, the first rotating element and the output member are connected, the first ring gear, the second carrier and the second rotation; The plurality of engagement mechanisms are detachably connected to the first clutch for detachably connecting the second sun gear and the input shaft, and the first carrier and the input shaft. A second clutch, a third clutch for releasably connecting the third rotating element and the input shaft, a first brake for releasably connecting the first carrier and the casing, and the first clutch 1 Sun gear and the casing A second brake for freely connecting, a third brake for detachably connecting the third rotating element and the casing, and a fourth brake for detachably connecting the fourth rotating element and the casing; And each of the plurality of engaging mechanisms is engaged to form each shift stage, and the first rotating element is configured by connecting the third carrier and the fourth carrier. The second rotating element is constituted by the third sun gear, the third rotating element is constituted by the fourth ring gear, and the fourth rotating element is connected to the third ring gear and the fourth sun gear. Ru is configured by the automatic transmission is provided, characterized in that.

  In the present invention, the value of each sun gear tooth number / ring gear tooth number of the first to fourth planetary gear mechanisms may be 0.3 or more and 0.7 or less.

  According to the present invention, it is possible to provide an automatic transmission in which the number of forward shift stages can be set to two digits without the λ value of the planetary gear mechanism being too large or too small.

The skeleton figure of the automatic transmission which concerns on 1st Embodiment. (A) is a figure which shows the example of the engagement table | surface of an engagement mechanism, (B) is a figure which shows (lambda) value of a planetary gear mechanism. The speed diagram of the automatic transmission of FIG. The skeleton figure of the automatic transmission which concerns on 2nd Embodiment. (A) is a figure which shows (lambda) value of a planetary gear mechanism, (B) is a speed diagram of the automatic transmission of FIG.

<First Embodiment>
FIG. 1 is a skeleton diagram of an automatic transmission 1 according to an embodiment of the present invention. The automatic transmission 1 includes an input shaft 10 that is rotatably supported in a casing 12 that constitutes the transmission case, and an output member 11 that is rotatably supported coaxially with the input shaft 10.

  The input shaft 10 receives power from a drive source (not shown) such as an internal combustion engine or an electric motor, and the input shaft 10 is rotated by the power. A starting device can be provided between the input shaft 10 and the driving source. Examples of the starting device include a clutch-type starting device (such as a single-plate clutch and a multi-plate clutch) and a fluid coupling-type starting device (such as a torque converter).

  The output member 11 includes an output gear concentric with the input shaft 10, and the rotation of the input shaft 10 is changed by a transmission mechanism described below and transmitted to the output member 11. The rotation of the output member 11 is transmitted to the drive wheels via, for example, a counter shaft (not shown) and a differential gear device.

  The automatic transmission 1 includes planetary gear mechanisms P1 to P4 and engagement mechanisms CL1 to CL3 and BR1 to BR4 as transmission mechanisms. In the present embodiment, the planetary gear mechanisms P1 to P4 are all single-pinion type planetary gear mechanisms.

  A total of 12 rotating elements are provided. The planetary gear mechanisms P1 to P4 include sun gears S1 to S4, ring gears R1 to R4, and carriers C1 to C4 that support pinion gears as rotational elements, and are arranged coaxially with the input shaft 10.

  The engagement mechanisms CL1 to CL3 and BR1 to BR4 can release either the predetermined rotation element of the planetary gear mechanisms P1 to P4 and the input shaft 10, or the predetermined rotation element and the casing 12. Connect to In the present embodiment, the engagement mechanisms CL1 to CL3 are clutches, and the engagement mechanisms BR1 to BR4 are brakes. The engagement mechanisms CL1 to CL3 and BR1 to BR4 can be switched between the engaged state (fastened state) and the released state, and the power transmission path from the input shaft 10 to the output member 11 is switched. The driving force input to the input shaft 10 can be output to the output member 12 at a gear ratio according to the combination of engagement and disengagement of these engagement mechanisms, and a plurality of shift speeds are realized.

  In this embodiment, the engagement mechanisms CL1 to CL3 and BR1 to BR4 are all assumed to be frictional hydraulic engagement mechanisms. Examples of the frictional hydraulic engagement mechanism include a wet multi-plate clutch.

  Next, the connection relationship between the components will be described with reference to FIG.

  The ring gear R1 of the planetary gear mechanism P1 and the carrier C2 of the planetary gear mechanism P2 are connected via a connecting member J4. The carrier C1 of the planetary gear mechanism P1 and the ring gear R2 of the planetary gear mechanism P2 are connected via a connecting member J3.

  The engagement mechanism BR1 couples the carrier C1, the ring gear R2, and the casing 12 through the coupling member J2 so as to be detachable. The engagement mechanism BR2 detachably connects the sun gear S1 of the planetary gear mechanism P1 and the casing 12 via the connecting member J1. The engagement mechanism CL2 removably couples the carrier C1, the ring gear R2, and the input shaft 10 via the coupling member J3. The engagement mechanism CL1 detachably connects the sun gear S2 of the planetary gear mechanism P2 and the input shaft 10 via the connecting member J5.

  The planetary gear mechanism P3 and the planetary gear mechanism P4 are constituted by connecting two of the rotating elements, and each of the rotating planetary gear mechanisms P4 includes a first to a fourth rotating element and a single planetary gear mechanism having four rotating elements. Is configured.

  The ring gear R3 of the planetary gear mechanism P3 and the carrier C4 of the planetary gear mechanism P4 are connected via a connecting member J8 to constitute the first rotating element of the compound planetary gear mechanism. The carrier C4 is further connected to the output member 11 via a connecting member J7.

  The sun gear S3 of the planetary gear mechanism P3 and the sun gear S4 of the planetary gear mechanism P4 are connected via a connecting member J6, and constitute a second rotating element of the compound planetary gear mechanism. The sun gear S4 is further connected to the carrier C2 of the planetary gear mechanism P2 via a connecting member J6.

  The carrier C3 of the planetary gear mechanism P3 constitutes a third rotating element of the compound planetary gear mechanism. The engagement mechanism CL3 detachably connects the carrier C3 and the input shaft 10 via the connecting member J9. The engagement mechanism BR3 detachably connects the carrier C3 and the casing 12 via the connecting member J9.

  The ring gear R4 of the planetary gear mechanism P4 constitutes the fourth rotating element of the compound planetary gear mechanism. The engagement mechanism BR4 connects the ring gear R4 and the casing 12 so as to be freely disengaged.

  2A is an engagement table (engagement table) of the engagement mechanisms CL1 to CL3 and BR1 to BR4 included in the automatic transmission 1, and FIG. 2B is a diagram of the planetary gear mechanisms P1 to P4 included in the automatic transmission 1. λ value (number of sun gear teeth / number of ring gear teeth), FIG. 3 is a speed diagram (collinear diagram) of the automatic transmission 1.

  In the example of the engagement table in FIG. 2A, “◯” indicates an engaged state (a state in which the components are connected), and no mark indicates a released state. “Gear ratio” indicates the gear ratio between the input shaft 10 and the output member 11.

  In the automatic transmission 1, at least three of the engagement mechanisms CL1 to CL3 and BR1 to BR4 (all three in the present embodiment) are engaged at each shift stage, so that the forward 10 stages and the reverse 1 The number of shift stages (RVS) is realized. The number of engagement mechanisms in the disengaged state at each shift stage is relatively small (four in this embodiment), and friction loss can be reduced.

  The speed diagram of FIG. 3 shows the rotational speed ratio of each element at each gear position with respect to the input to the input shaft 10. The vertical axis indicates the speed ratio, “1” indicates the same rotational speed as the input shaft 10, and “0” indicates the stop state. The horizontal axis is based on the λ values of the planetary gear mechanisms P1 to P4.

  As shown in FIG. 2A, in the present embodiment, a general ratio setting suitable for each gear position is performed. Nevertheless, as shown in FIG. 2B, in this embodiment, the λ values of the planetary gear mechanisms P1 to P4 are in the range of 0.40 to 0.67, which is generally considered to be 0. .3 or more and 0.7 or less. That is, the forward shift speed can be set to two digits (here, 10 speeds) without the λ values of the planetary gear mechanisms P1 to P4 being too large or too small.

Second Embodiment
Another configuration example in which the planetary gear mechanism, the number of engagement mechanisms, and the gear ratio are the same as those in the first embodiment will be described. FIG. 4 is a skeleton diagram of the automatic transmission 1 according to the present embodiment. The automatic transmission 1 of the present embodiment is basically the same as the component in the first embodiment, and the corresponding components are denoted by the same reference numerals. About the connection relationship between each component in the automatic transmission 1 of this embodiment, the planetary gear mechanisms P1 and P2 and the engagement mechanisms CL1, CL2, BR1, and BR2 are the same as those in the first embodiment. Hereinafter, different points will be described.

  The planetary gear mechanism P3 and the planetary gear mechanism P4 are constituted by connecting two of the rotating elements, and each of the rotating planetary gear mechanisms P4 includes a first to a fourth rotating element and a single planetary gear mechanism having four rotating elements. Is configured.

  The carrier C3 of the planetary gear mechanism P3 and the carrier C4 of the planetary gear mechanism P4 are connected via a connecting member J13, and constitute a first rotating element of the compound planetary gear mechanism. The carrier C3 and the carrier C4 are further connected to the output member 11 via a connecting member J12.

  The sun gear S3 of the planetary gear mechanism P3 constitutes the second rotating element of the compound planetary gear mechanism. The sun gear S3 and the carrier C2 of the planetary gear mechanism P2 are connected via a connecting member J11.

  The ring gear R4 of the planetary gear mechanism P4 constitutes a third rotating element of the compound planetary gear mechanism. The engagement mechanism BR3 detachably connects the ring gear R3 and the casing 12 via the connecting member J15. The engagement mechanism CL3 detachably connects the ring gear R4 and the input shaft 10 via the connecting member J15.

  The ring gear R3 of the planetary gear mechanism P3 and the sun gear S4 of the planetary gear mechanism P4 are connected via a connecting member J14 to constitute the fourth rotating element of the compound planetary gear mechanism. The engagement mechanism BR4 detachably connects the ring gear R3 and sun gear S4 and the casing 12 via the connecting member J14.

  The engagement table (engagement table) of the engagement mechanisms CL1 to CL3 and BR1 to BR4 included in the automatic transmission 1 of the present embodiment is the same as that of the first embodiment including the gear ratio (FIG. 2A).

  5A is a λ value (the number of sun gear teeth / the number of ring gear teeth) of the planetary gear mechanisms P1 to P4 in the present embodiment, and FIG. 5B is a velocity diagram (collinear) of the automatic transmission 1 in the present embodiment. Figure).

  As shown in FIG. 5A, the λ values of the planetary gear mechanisms P1 to P4 are in the range of 0.50 to 0.67, and are 0.3 or more and 0, which is generally preferable also in this embodiment. Within the range of 7 or less. That is, the forward shift speed can be set to two digits (here, 10 speeds) without the λ values of the planetary gear mechanisms P1 to P4 being too large or too small.

Claims (3)

An input shaft that rotates by a driving force from a driving source;
A plurality of planetary gear mechanisms having rotating elements composed of a sun gear, a carrier, and a ring gear;
A plurality of engagement mechanisms capable of connecting either the rotating element and the input shaft or the rotating element and the casing;
In an automatic transmission that outputs a driving force input from a driving source to the input shaft to an output member at a gear ratio according to a combination of engagement and disengagement of the engagement mechanism,
The plurality of planetary gear mechanisms includes:
A first planetary gear mechanism including a first sun gear, a first carrier, and a first ring gear;
A second planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear;
A third planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear;
A fourth planetary gear mechanism including a fourth sun gear, a fourth carrier, and a fourth ring gear,
The third planetary gear mechanism and the fourth planetary gear mechanism are constituted by connecting two of the rotating elements, respectively, and constitute a compound planetary gear mechanism having first to fourth rotating elements,
The first carrier and the second ring gear are coupled;
The first rotating element and the output member are coupled;
The first ring gear, the second carrier, and the second rotating element are coupled;
The plurality of engagement mechanisms are:
A first clutch that releasably connects the second sun gear and the input shaft;
A second clutch detachably connecting the first carrier and the input shaft;
A third clutch for releasably connecting the third rotating element and the input shaft;
A first brake for releasably connecting the first carrier and the casing;
A second brake for releasably connecting the first sun gear and the casing;
A third brake for releasably connecting the third rotating element and the casing;
A fourth brake for releasably connecting the fourth rotating element and the casing;
Each shift stage is formed by engaging at least three of the plurality of engagement mechanisms,
The first rotating element is configured by connecting the third ring gear and the fourth carrier,
The second rotating element is configured by connecting the third sun gear and the fourth sun gear,
The third rotating element is composed of the third carrier,
The fourth rotating element is composed of the fourth ring gear.
An automatic transmission characterized by that. An input shaft that rotates by a driving force from a driving source;
A plurality of planetary gear mechanisms having rotating elements composed of a sun gear, a carrier, and a ring gear;
A plurality of engagement mechanisms capable of connecting either the rotating element and the input shaft or the rotating element and the casing;
In an automatic transmission that outputs a driving force input from a driving source to the input shaft to an output member at a gear ratio according to a combination of engagement and disengagement of the engagement mechanism,
The plurality of planetary gear mechanisms includes:
A first planetary gear mechanism including a first sun gear, a first carrier, and a first ring gear;
A second planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear;
A third planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear;
A fourth planetary gear mechanism including a fourth sun gear, a fourth carrier, and a fourth ring gear,
The third planetary gear mechanism and the fourth planetary gear mechanism are constituted by connecting two of the rotating elements, respectively, and constitute a compound planetary gear mechanism having first to fourth rotating elements,
The first carrier and the second ring gear are coupled;
The first rotating element and the output member are coupled;
The first ring gear, the second carrier, and the second rotating element are coupled;
The plurality of engagement mechanisms are:
A first clutch that releasably connects the second sun gear and the input shaft;
A second clutch detachably connecting the first carrier and the input shaft;
A third clutch for releasably connecting the third rotating element and the input shaft;
A first brake for releasably connecting the first carrier and the casing;
A second brake for releasably connecting the first sun gear and the casing;
A third brake for releasably connecting the third rotating element and the casing;
A fourth brake for releasably connecting the fourth rotating element and the casing;
Each shift stage is formed by engaging at least three of the plurality of engagement mechanisms,
The first rotating element is configured by connecting the third carrier and the fourth carrier,
The second rotating element is constituted by the third sun gear,
The third rotating element is composed of the fourth ring gear,
The fourth rotating element is configured by connecting the third ring gear and the fourth sun gear.
An automatic transmission characterized by that. The automatic transmission according to claim 1 or 2 , wherein
Each sun gear tooth number / ring gear tooth number value of the first to fourth planetary gear mechanisms is 0.3 or more and 0.7 or less,
An automatic transmission characterized by that.

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