JP6221626B2 - Automatic transmission for vehicles - Google Patents

Description

  The present invention relates to an automatic transmission for a vehicle that shifts the rotation of an input shaft that is rotationally driven by a vehicle engine or the like to a plurality of shift speeds and transmits it to an output shaft.

  For example, the automatic transmission for a vehicle described in Patent Document 1 shown below is composed of four single pinion planetary mechanisms and six engagement elements, that is, two brakes and four clutches, of which three elements are Engaging with each other forms a shift stage of 10 forward speeds and 1 reverse speed. As shown in FIG. 7, the first to fourth planetary mechanisms P11 to P14 are sequentially arranged in parallel from the input shaft N side to the output shaft T side. In the following description, the members constituting the first to fourth planetary mechanisms P11 to P14 are the first to fourth carriers C11 to C14 and the first to fourth sun gears S11 that support the first to fourth pinions Q11 to Q14. To S14 and first to fourth ring gears R11 to R14.

  The second carrier C12 is connected to the input shaft N, and the fourth carrier C14 can be selected to be connected to the input shaft N by the first clutch CL11. The second sun gear S12 is connected to the first sun gear S11, and the connection to the housing H can be selected by the first brake B11. The second ring gear R12 is connected to the first carrier C11 and can be selected to be connected to the third ring gear R13 by the second clutch CL12.

  The second ring gear R12 can be connected to the third sun gear S13 and the fourth sun gear S14 by the third clutch CL13. The first ring gear R11 can be connected to the third sun gear S13 and the fourth sun gear S14 by the fourth clutch CL14. The third ring gear R13 can be selected to be connected to the housing H by the second brake B12. The third carrier C13 is connected to the fourth ring gear R14 and the output shaft T.

  In FIG. 8, the torque sharing ratios of the respective clutches CL11 to CL14 and the respective brakes B11 and B12 corresponding to the respective shift speeds are shown. When numerical values are given in the columns, the clutch CL11 to CL14 are in the connected state, The brakes B11 and B12 indicate that the rotation is restricted. The numerical value in each column is the torque sharing ratio when the input torque is “1.000”.

US20090054196

  In the vehicular automatic transmission 10 disclosed in Patent Document 1, the torque sharing ratio of the third clutch CL13 is “1.875” at the first speed and the first at the fifth speed as shown in the torque sharing ratio of FIG. The torque sharing ratio of the clutch CL11 is “1.974”, the torque sharing ratio of the first clutch CL11 is “1.571” at the sixth speed, and the torque sharing ratio of the second clutch CL12 is “1.875” at the reverse time. Since it exceeds “1.000”, three of the six engagement elements, that is, the first, second, and third clutches CL11, CL12, and CL13 tend to be large.

  In addition, when performing power take-off (hereinafter simply referred to as PTO) for extracting engine power for driving a vehicle for driving a work machine in a commercial vehicle such as a dump truck or a fire truck, it is connected to input rotation from the engine. It is necessary to provide a power external take-out member to the connecting member of the element. In the automatic transmission 10 for a vehicle shown in Patent Document 1, the second carrier C12 connected to the input rotation from the engine is not positioned near the inner peripheral surface of the housing H. In order to be able to use the PTO even at the shift stage, a mechanism for directly extracting the input rotation from the engine is required between the engine and the first planetary mechanism P11, and the number of parts and the axial length must be increased. I do not get.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an automatic transmission for a vehicle that can reduce the number of clutches that increase in size.

In order to solve the above-described problem, in a vehicle automatic transmission according to a first aspect, a housing, a first ring gear of a first planetary gear, and a second ring gear of a second planetary gear are directly connected to each other, and the first ring gear and the first ring gear A single pinion in which the two ring gear and the fourth sun gear of the fourth planetary gear are directly connected, the third ring gear of the third planetary gear and the fourth carrier of the fourth planetary gear are directly connected, and are supported on the housing coaxially with the rotation axis. and four planetary gears of the formula, is rotatably journalled on the axis of rotation in said housing, said direct coupling input shaft to the first carrier of the first planetary gear rotatably journalled on the axis of rotation in said housing And an output shaft directly connected to the fourth carrier, and a first sun gear of the first planetary gear A first brake for releasably fixing to the housing; a second brake for releasably fixing a fourth ring gear of the fourth planetary gear to the housing; the first and second ring gears directly connected to each other; A first clutch for releasably connecting the fourth sun gear and the third carrier of the third planetary gear, and a second sun gear of the second planetary gear and a third sun gear of the third planetary gear are releasably connected. A second clutch; a third clutch for releasably connecting the third carrier and the fourth ring gear; the first carrier and the second planetary gear second carrier and the third sun gear directly connected to each other; And a fourth clutch for detachably connecting the clutch.

  According to this configuration, the torque sharing ratio of the first clutch and the second clutch can be made smaller than the input torque, and the torque sharing ratio may be larger than the input torque. Only the clutch. Therefore, the number of clutches that increase in size can be reduced, and the vehicle automatic transmission can be reduced in size.

  In order to solve the above-mentioned problem, an automatic transmission for a vehicle according to a second aspect is the vehicle automatic transmission according to the first aspect, wherein the first to fourth planetary gears are sequentially parallel in this order from the input shaft side to the output shaft side. The first carrier is directly connected to the input shaft directly connected to the input shaft and passing through the inside of the first sun gear on the output shaft side, and is directly connected to the second carrier and the first carrier. And the gear coupling member passing outside the second ring gear is directly coupled on the input shaft side, and the fourth clutch is coupled to the first and second clutches via the fourth clutch coupling member coupled directly to the gear coupling member. A carrier and the third sun gear are detachably connected, and a power external take-out member for taking out power to the outside is provided outside the first and second ring gears in the gear connecting member. The the gist.

  According to this, the first sun gear engages with the connecting member and other engaging elements for connecting with other planetary mechanism elements, except for connecting with the brake connecting member for engaging with the first brake. The connection with the connection member for doing is unnecessary. For this reason, the gear coupling member coupled to the first carrier directly coupled to the input shaft can pass through a path located in the vicinity of the inner peripheral surface of the housing. Therefore, it is possible to always extract the power of the same rotation as the input rotation as the PTO from the gear coupling member coupled to the first carrier regardless of the gear position.

  In order to solve the above problem, an automatic transmission for a vehicle according to a third aspect of the present invention is the automatic transmission for a vehicle according to the first aspect, wherein the second planetary gear, the first planetary gear, the third planetary gear, and the fourth planetary gear are The second to fourth clutches are arranged on the outer diameter side in the housing, and the second and first carriers are directly connected to the input shaft. The second direct clutch is directly connected to the input direct connection member passing through the inside of the second and first sun gears on the output shaft side, and the second clutch is directly connected to the third sun gear and passes through the outer sides of the second and first ring gears. The second sun gear and the third sun gear are detachably connected via a two-clutch connecting member, and the fourth clutch is connected to the second clutch connecting member directly. Through the clutch coupling member, and summarized in that for connecting the third sun gear and the second and the first carrier detachably.

  According to this, since the second clutch and the fourth clutch can be arranged on the outer diameter side in the housing, the torque capacity input from the input shaft can be increased. Therefore, the size of the second clutch and the fourth clutch can be reduced.

1 is a skeleton diagram schematically showing a first embodiment of an automatic transmission for a vehicle of the present invention. It is a figure which shows the operating state of the brake and clutch in each gear stage of 1st Embodiment. It is a speed diagram which shows the rotation ratio of each element of the planetary mechanism in each gear position of 1st Embodiment. It is a skeleton figure of the automatic transmission for vehicles of a 2nd embodiment. It is a figure which shows the operating state of the brake and clutch in each gear stage of 2nd Embodiment. It is a speed diagram which shows the rotation ratio of each element of the planetary mechanism in each gear position of 2nd Embodiment. It is a skeleton figure of the conventional automatic transmission for vehicles. It is a figure which shows the operating state of the brake and clutch in each conventional gear stage.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment in which an automatic transmission for a vehicle according to the present invention is embodied will be described with reference to the drawings. In the embodiment, the vehicular automatic transmission is used as a device that shifts a rotational driving force output from an engine mounted on the vehicle. The vehicle is configured such that the rotational driving force shifted by the vehicle automatic transmission is transmitted to the drive wheels via a differential device or the like, and moves forward or backward at a predetermined shift stage established in the vehicle automatic transmission. ing.

<First Embodiment>
A schematic configuration of the vehicle automatic transmission 1 will be described with reference to FIG. The vehicle automatic transmission 1 selects four planetary mechanisms P1 to P4 arranged in parallel in the axial direction from the input side (left side in FIG. 1) to the output side (right side in FIG. 1), and a plurality of elements. Four clutches CL1 to CL4 that can be connected to each other, two second brakes B1 and B2 that brake the rotation of a predetermined element, and connecting members 3 to 8, V1, V2, U11, U12, U21, U22, U31, U32, U41, U42, an input shaft N, and an output shaft T are provided.

  In the vehicular automatic transmission 1, the operating state of the engaging elements including the clutches CL1 to CL4 and the brakes B1 and B2 is controlled based on a control signal from the control ECU 2 of the vehicle. In the present embodiment, by operating three engaging elements among the above engaging elements, the rotational driving force input from the input shaft N is set to one of the 10th forward speed and the first reverse speed. So that the output shaft T can output. Details regarding the operating state of the engagement element and the established gear stage in the vehicle automatic transmission 1 will be described later.

  The input shaft N and the output shaft T are supported by the housing H so as to be rotatable around the rotation axis L. The input shaft N is a shaft member that inputs the rotational driving force of the engine to the vehicle automatic transmission 1 via a clutch device (not shown). The output shaft T is a shaft member that is arranged on the same axis as the input shaft N, and that outputs a rotational drive force that has been shifted to a drive wheel via a differential device (not shown).

  Each planetary mechanism P1 to P4 is a single pinion type in which pinion gears rotatably supported by carriers C1 to C4 are engaged with sun gears S1 to S4 and ring gears R1 to R4. These are referred to as P1 to P4. The elements of the planetary mechanisms P1 to P4 are referred to as first to fourth sun gears S1 to S4, first to fourth ring gears R1 to R4, and first to fourth carriers C1 to C4.

The first planetary mechanism P1 supports the first sun gear S1, the first ring gear R1, and the first pinion Q1 meshing with the first sun gear S1 and the first ring gear R1, which are rotatably supported coaxially with the rotation axis L. The first carrier C1 is configured.
The second planetary mechanism P2 supports the second sun gear S2, the second ring gear R2, and the second pinion Q2 meshing with the second sun gear S2 and the second ring gear R2 that are rotatably supported coaxially with the rotation axis L. Configured with the second carrier C2.

The third planetary mechanism P3 supports the third sun gear S3, the third ring gear R3, and the third pinion Q3 meshing with the third sun gear S3 and the third ring gear R3, which are rotatably supported coaxially with the rotation axis L. The third carrier C3.
The fourth planetary mechanism P4 supports the fourth sun gear S4, the fourth ring gear R4, and the fourth pinion Q4 meshing with the fourth sun gear S4 and the fourth ring gear R4, which are rotatably supported coaxially with the rotation axis L. The fourth carrier C4.

  Each brake B1, B2 is an engagement element that is provided in the housing H and brakes the rotation of a predetermined element. In the present embodiment, similar to the clutches C1 to C4, the hydraulic system is operated by the hydraulic pressure supplied from the oil passage formed in the housing H. Thus, when the hydraulic pressure is supplied from the hydraulic pump that operates based on a control command from the control ECU 2, for example, each of the brakes B1 and B2 presses a pad against a disk (not shown) to rotate a predetermined target element. Braking. When the supply of hydraulic pressure by the hydraulic pump is interrupted, the pad is separated from the disk to allow rotation of a predetermined element.

  Each of the clutches CL1 to CL4 is an engagement element that can selectively connect a plurality of elements. In the present embodiment, each of the clutches CL1 to CL4 is a normally open type and is a hydraulic type that is operated by supplied hydraulic pressure. As a result, each of the clutches CL1 to CL4 is supplied with hydraulic pressure via an oil passage formed in the input shaft N or the housing H from a hydraulic pump that operates based on a control command from the control ECU 2, for example. The clutch plates are brought into contact with each other so that the driving force is transmitted between the target elements. When the hydraulic pressure supply by the hydraulic pump is interrupted, the clutch plates are separated from each other so that the elements are separated from each other so that the driving force is not transmitted between the target elements.

The input shaft N is directly connected to the first carrier C1 via an input shaft connecting member 3 that extends in the axial direction through the inside of the first sun gear S1.
The output shaft T is directly connected to the fourth carrier C4 via the output shaft connecting member 4.
The first carrier C1 and the second carrier C2 are provided with a first gear connecting member 5 (corresponding to the “gear connecting member” of the present invention) extending in the axial direction through the outside of the first and second ring gears R1, R2. It is connected directly through. The first gear connecting member 5 is provided with a power external takeout member M for taking out the power to the outside.

The first ring gear R1 and the second ring gear R2 are directly connected via the second gear connecting member 6. The first and second ring gears R1, R2 and the fourth sun gear S4 are directly connected to the second gear connecting member 6 and extend in the axial direction through the insides of the second and third sun gears S2, S3. It is directly connected via the connecting member 7.
The third ring gear R3 and the fourth carrier C4 are directly connected via the fourth gear coupling member 8.

The first brake B1 brakes the rotation of the first sun gear S1 directly connected to the first brake connecting member V1 via the first brake connecting member V1.
The second brake B2 brakes the rotation of the fourth ring gear R4 directly connected to the second brake connecting member V2 via the second brake connecting member V2.
Since the first brake B1 is disposed on the first planetary mechanism P1 side and the second brake B2 is disposed on the fourth planetary mechanism P4 side, the first brake B1 is disposed between the first and second brakes B1 and B2. Four clutches CL1 to CL4 can be arranged.

The first clutch CL1 is directly connected to the third carrier C3 via the first clutch coupling member U11 on the output shaft T side, and extends in the axial direction through the insides of the second and third sun gears S2, S3. The third carrier C3 and the first and second ring gears R1 and R2 are detachably connected via the one clutch connecting member U12.
The second clutch CL2 is directly coupled to the second sun gear S2 via the second clutch coupling member U21, and the second sun gear S2 and the third sun gear S3 are detachably coupled via the second clutch coupling member U22. To do.

The third clutch CL3 is directly coupled to the fourth ring gear R4 via a third clutch direct coupling member U31 extending in the axial direction through the outside of the third ring gear R3, and the third clutch coupling member U32 on the input shaft N side. The fourth ring gear R4 and the third carrier C3 are detachably connected via the. The third clutch CL3 can be disposed on the inner peripheral surface Ha side of the housing H between the second planetary mechanism P2 and the third planetary mechanism P3. Therefore, the third clutch CL3 itself can be reduced in size.
The fourth clutch CL4 is directly coupled to the first gear coupling member 5 via the fourth clutch direct coupling member U41, and is coupled to the first clutch via the fourth clutch coupling member U42 coupled directly to the second clutch coupling member U22. The second carriers C1, C2 and the third sun gear S3 are detachably connected.

  The vehicle automatic transmission 1 configured as described above selectively disengages and disengages the first to fourth clutches CL1 to CL4 and selectively operates the first and second brakes B1 and B2. By restricting the rotation of the elements of the fourth planetary mechanisms P1 to P4, it is possible to establish 10 forward speeds and 1 reverse speed. In FIG. 2, the torque sharing ratios of the respective clutches CL1 to CL4 and the respective brakes B1 and B2 corresponding to the respective shift speeds are shown. When numerical values are given in the columns, the clutch CL1 to CL4 is in the connected state, The brakes B1 and B2 indicate that the rotation is restricted. The numerical value in each column is the torque sharing ratio when the input torque is “1.000”.

In general, in the single pinion type planetary mechanism, the relationship among the rotational speed Ns of the sun gear, the rotational speed Nc of the carrier, the rotational speed Nr of the ring gear, and the gear ratio λ of the planetary gear mechanism is expressed by Equation (1). The gear ratio at each gear stage is calculated based on the equation (1). If the number of teeth of the first to fourth sun gears S1 to S4 of the first to fourth planetary mechanisms P1 to P4 is Zs1 to Zs4, and the number of teeth of the first to fourth ring gears R1 to R4 is Zr1 to Zr4, The gear ratios λ1 to λ4 of the fourth planetary mechanisms P1 to P4 are λ1 = Zs1 / Zr1, λ2 = Zs2 / Zr2, λ3 = Zs3 / Zr3, and λ4 = Zs4 / Zr4.
Nr = (1 + λ) Nc−λNs (1)

  When the first and second brakes B1 and B2 are selectively operated and the first to fourth clutches CL1 to CL4 are selectively connected, the speed ratio of each element of the first to fourth planetary mechanisms P1 to P4 is FIG. 3 is a velocity diagram. The speed diagram shows the planetary mechanism's sun gear, carrier, and ring gear elements arranged at intervals corresponding to the gear ratio in the horizontal axis direction and the speed ratio corresponding to each element in the vertical axis direction. It is.

  That is, since the second sun gear S2 and the third sun gear S3 are connected via the second clutch CL2, the second sun gear S2 and the third sun gear S2 and the third sun gear S2 that are connected on one vertical line with S2 and S3 attached thereto. It represents the speed ratio of the sun gear S3. Further, since the second ring gear R2, the third carrier C3 and the fourth sun gear S4 are connected via the first clutch CL1, they are connected on one vertical line with R2, C3 and S4. The speed ratio of the second ring gear R2, the third carrier C3, and the fourth sun gear S4 is represented. Then, the speed ratio of the second carrier C2 is represented on one line with C2. In addition, since the third carrier C3 and the fourth ring gear R4 are connected via the third clutch CL3, the third carrier C3 and the fourth connected to one vertical line to which C3 and R4 are attached. It represents the speed ratio of the ring gear R4.

  Since the second planetary mechanism P2 is of a single pinion type, the interval between the vertical line of the second sun gear S2 and the vertical line of the second carrier C2 is regarded as 1, and the vertical line of the second ring gear R2 is regarded as the second carrier. The second sun gear S2 is arranged on the opposite side of the vertical line of C2 from the vertical line by a distance λ2. Since the third planetary mechanism P3 is of a single pinion type, the interval between the vertical line of the third sun gear S3 and the vertical line of the third carrier C3 is regarded as 1, and the vertical line of the third ring gear R3 is defined as the third carrier C3. Arranged at a distance λ3 away from the vertical line on the opposite side of the vertical line of the third sun gear S3. Since the fourth planetary mechanism P4 is a single pinion type, the interval between the vertical line of the fourth sun gear S4 and the vertical line of the fourth carrier C4 is regarded as 1, and the vertical line of the fourth ring gear R4 is defined as that of the fourth carrier C4. The vertical line is spaced apart from the vertical line of the fourth sun gear S4 by a distance λ4.

  For example, according to the engagement table, the first speed in the vehicular automatic transmission 1 is such that the operating states of the first clutch CL1, the second clutch CL2, and the second brake B2 are ON. The second sun gear S2 and the third sun gear S3 rotate integrally with the engagement of the second clutch CL2, and the second ring gear R2, the third carrier C3, and the fourth sun gear S4 rotate with the engagement of the first clutch CL1. . Since the fourth ring gear R4 is braked by the second brake B2, the rotational driving force input to the second carrier C2 is decelerated at a gear ratio corresponding to the number of teeth of the second to fourth planetary mechanisms P2 to P4. The rotational driving force is transmitted from the fourth carrier C4 to the output shaft T through the output shaft connecting member 72.

  In order for the vehicle automatic transmission 1 to shift from the first speed to the second speed, the engaging element to be operated is maintained from the first clutch CL1 while maintaining the operating state of the second clutch CL2 and the second brake B2. Switch to the fourth clutch CL4. In such an engaged state, first, the first and second planetary mechanisms P1, P2 are integrated by the second clutch CL2 and the fourth clutch CL4, and the rotational driving force of the input shaft N input to the second ring gear R2 is obtained. , Transmitted to the fourth sun gear S4. Since the fourth ring gear R4 is braked by the second brake B2, the rotational driving force input from the fourth sun gear S4 is decelerated at a gear ratio corresponding to the number of teeth, and the output shaft connecting member 72 is moved from the fourth carrier C4. The rotational driving force is transmitted to the output shaft T via

  As described above, the vehicle automatic transmission 1 has three different gear ratios as shown in the velocity diagram of FIG. 3 by selectively operating three of the six engagement elements. The gear stage can be established. Further, as shown in the engagement table of FIG. 2, the transmission 1 can shift to an adjacent shift stage by switching one of the three engagement elements to be operated.

  Here, generally, the clutch provided on the carrier tends to be large. In order to avoid an increase in the size of the clutch, the vehicle automatic transmission 1 may be configured so that the torque sharing ratio of the clutch is reduced. A method for calculating the torque sharing ratio of the clutch will be described in the case of the first gear stage in the conventional automatic transmission 10 for vehicles and the automatic transmission 1 for vehicles of the present embodiment.

First, the case of the first shift stage in the conventional vehicle automatic transmission 10 will be described with reference to FIGS. In the first gear, the operating states of the third clutch CL13, the fourth clutch CL14, and the second brake B12 are ON. When the number of teeth of the first and second sun gears S11 and S12 and the first and second ring gears R11 and R12 is Z ₁₁ s, Z ₁₂ s, Z ₁₁ r, and Z ₁₂ r, the first and second planetary mechanisms P11 are used. and the gear ratio [rho ₁₁ of _P12, [rho ₁₂ to _{Z 11 r} / _Z 11 _s, and _{Z 12} r _/ Z 12 s. The torque sharing ratios of the first and second sun gears S11 and S12, the first and second ring gears R11 and R12, and the first and second carriers C11 and C12 are set to T ₁₁ s, T ₁₂ s, T ₁₁ r, and T ₁₂ r, respectively. T ₁₁ c and T ₁₂ c are assumed.

Since the rotational driving force (referred to as “1.000”) of the input shaft N is input to the second carrier C12, T ₁₂ c is expressed by the following equation (1). Therefore, T ₁₂ r is represented by the following equation (2), and T ₁₂ s is represented by the following equation (3).

T ₁₂ c = −1 (1)
T ₁₂ r = ρ ₁₂ / (ρ ₁₂ +1) (2)
T ₁₂ s = 1 / (ρ ₁₂ +1) (3)

Since the first and second sun gears S11 and S12 are directly connected, T ₁₁ s is expressed by the following equation (4), and T ₁₁ c is expressed by the following equation (5).

T ₁₁ s = −T ₁₂ s = −1 / (ρ ₁₂ +1) (4)
T ₁₁ c = −T ₁₁ s · (ρ ₁₁ +1) = (ρ ₁₁ +1) / (ρ ₁₂ +1) (5)

Therefore, the torque sharing ratio Tcl ₁₃ of the third clutch CL13 is expressed by the following equation (6).

Tcl ₁₃ = T ₁₂ r + T ₁₁ c = (ρ ₁₁ + ρ ₁₂ +1) / (ρ ₁₂ +1) (6)

By substituting a predetermined numerical value into the torque sharing ratio Tcl ₁₃ of the third clutch CL13 expressed by the equation (6), “1.875” is obtained as shown in FIG. Hereinafter, by applying the same calculation method to each gear, the torque sharing ratio of the first to third clutches CL11 to 13 becomes “1.000” or more, and the first to third clutches CL11 to 13 are increased in size. To do.

Next, the case of the first shift stage in the vehicle automatic transmission 1 of the present embodiment will be described with reference to FIGS. 1 and 2. In the first gear, the operating states of the first clutch CL1, the second clutch CL2, and the second brake B2 are ON. When the number of teeth of the first and second sun gears S1 and S2 and the first and second ring gears R1 and R2 is Z ₁ s, Z ₂ s, Z ₁ r, and Z ₂ r, the first and second planetary mechanisms P1 and the gear ratio [rho ₁ of _P2, [rho ₂ to _{Z 1 r} / _Z 1 _s, and _{Z 2} r / Z 2 s. The torque sharing ratios of the _{first and} second sun gears S1 and S2, the first and second ring gears R1 and R2, and the first and second carriers C1 and C2 are set to T ₁ s, T ₂ s, T ₁ r, T ₂ r, Let T ₁ c and T ₂ c.

Since the rotational driving force of the input shaft N (referred to as “1.000”) is input to the second carrier C2, T ₂ c is expressed by the following equation (7). Therefore, T ₂ s is expressed by the following equation (8).

T ₂ c = −1 (7)
T ₂ s = −T ₂ c / (ρ ₂ +1) = 1 / (ρ ₂ +1) (8)

Therefore, Equation (8) represents the torque sharing ratio Tcl ₂ of the second clutch CL2.
Since the second and third sun gears S2 and S3 are connected, T ₃ s is expressed by the following equation (9), and T ₃ c is expressed by the following equation (10).

T ₃ s = −T ₂ s = −1 / (ρ ₂ +1) (9)
T ₃ c = −T ₃ s · (ρ ₃ +1) = (ρ ₃ +1) / (ρ ₂ +1) (10)

Therefore, Expression (10) represents the torque sharing ratio Tcl ₁ of the first clutch CL1.
By substituting predetermined numerical values into the torque sharing ratios Tcl _{2 and} Tcl ₁ of the second and first clutches CL2 and CL1 represented by the equations (8) and (10), as shown in FIG. .238 "and" 0.952 ". Hereinafter, by applying the same calculation method to each gear stage, the torque sharing ratios Tcl _{2 and} Tcl _{1 of} the first and second clutches CL1 and CL2 become less than “1.000”, and the first and second clutches CL1 , CL2 can be reduced in size.

According to the vehicle automatic transmission 1 of the first embodiment, the torque sharing ratios Tcl _{2 and} Tcl _{1 of} the first clutch CL1 and the second clutch CL2 are made smaller than the input torque “1.000”. can be, there is a case where the torque sharing ratio Tcl ₃ becomes larger than the input torque "1.000" is only the third clutch CL3. Therefore, the number of clutches that are increased in size can be reduced, and the vehicle automatic transmission 1 can be reduced in size.

  Further, in the conventional vehicle automatic transmission 10 shown in FIG. 7, the element coupled to the input rotation from the engine is the second carrier C12. The second ring gear R12 drivingly connected to the second carrier C12 is drivingly connected to the first carrier C11, and the first carrier C11 is detachably connected to the second clutch CL12 on the input shaft N side. Has been. The second clutch CL12 is detachably connected to a second brake B12 fixed to the inner peripheral surface of the housing H. The second ring gear R12 is detachably connected to the third clutch CL13, and the first ring gear R11 is detachably connected to the fourth clutch CL14.

  On the other hand, the second sun gear S12 and the first sun gear S11, which are drivingly connected to the second carrier C12, are fixed to the inner peripheral surface of the housing H via the first connecting member 11 on the input shaft N side. The brake B11 is detachably connected. As described above, since the second carrier C12 connected to the input rotation from the engine is not positioned in the vicinity of the inner peripheral surface of the housing H, the PTO can be used at any gear stage during stopping and traveling. For this purpose, a mechanism for directly extracting the input rotation from the engine is required between the engine and the first planetary mechanism P11, and the number of parts and the axial length must be increased.

  However, in the vehicle automatic transmission 1 according to the first embodiment, the first sun gear S1 can be connected to the first brake connecting member V1 for engaging with the first brake B1, and other planetary gears can be used. It is not necessary to connect the connecting member for connecting with the elements of the mechanisms P2 to P4 and the connecting member for engaging with the other engaging elements B2, CL1 to CL4. For this reason, the first gear coupling member 5 coupled to the first carrier C1 directly coupled to the input shaft N can pass through a path located in the vicinity of the inner peripheral surface Ha of the housing H. Therefore, the power of the same rotation as the input rotation can always be taken out from the first gear connecting member 5 connected to the first carrier C1 by the power external take-out member M regardless of the gear position, and the PTO function is exhibited. To do.

Second Embodiment
In the vehicular automatic transmission 21 of the second embodiment, the first planetary mechanism P1 and the second planetary mechanism P2 in the vehicular automatic transmission 1 in the first embodiment are replaced, and the connection portion, the clutch, and the brake are not connected. A configuration different from the vehicle automatic transmission 1 according to the first embodiment will be described with reference to FIGS. 4 to 6.

In the vehicle automatic transmission 21, the second clutch CL <b> 2 and the fourth clutch CL <b> 4 are disposed at a position closer to the inner peripheral surface Ha of the housing H than the rotation axis L.
The second clutch CL2 extends in the axial direction through the outside of the second and first ring gears R2 and R1, and further passes through the second clutch coupling member U23 extending to the rotation axis L side, and thereby the third sun gear S3. The second sun gear S2 and the third sun gear S3 are detachably coupled to each other via a second clutch coupling member U24 that is directly coupled to the rotation axis L and extends to the rotation axis L side.

  The fourth clutch CL4 is directly connected to the third sun gear S3 via a fourth clutch direct connection member U43 directly connected to the second clutch connection member U23, and is connected to the first and second via the fourth clutch connection member U44. The carriers C1, C2 and the third sun gear S3 are detachably connected.

  Also in the vehicle automatic transmission 21 of the second embodiment configured as described above, the first to fourth clutches CL1 to CL4 are selectively engaged and disengaged similarly to the vehicle automatic transmission 1 of the first embodiment. The first and second brakes B1 and B2 are selectively operated to restrict the rotation of the elements of the first to fourth planetary mechanisms P1 to P4, thereby establishing 10 forward speeds and 1 reverse speed. be able to. The figure which shows the operating state of the brake and clutch in each gear stage of the automatic transmission 21 for vehicles of 2nd Embodiment shown in FIG. 5, and each gear stage of the automatic transmission 21 for vehicles of 2nd Embodiment shown in FIG. The speed diagram showing the rotation ratio of each element of the planetary mechanism is the same as in FIG. 2 and FIG.

According to the vehicle automatic transmission 21 of the second embodiment, the torque sharing ratios Tcl _{2 and} Tcl _{1 of} the first clutch CL1 and the second clutch CL2 are made smaller than the input torque “1.000”. can be, there is a case where the torque sharing ratio Tcl ₃ becomes larger than the input torque "1.000" is only the third clutch CL3. Therefore, the number of clutches CL1 and CL2 that increase in size can be reduced, and the vehicle automatic transmission 21 can be reduced in size.

  Further, the second clutch CL2 and the fourth clutch CL4 can be configured to be disposed on the outer diameter side in the housing H. Therefore, the torque capacity input from the input shaft N can be increased. And when making it the same as the existing torque capacity | capacitance without enlarging torque capacity, since 2nd clutch CL2 and 4th clutch CL4 can be reduced in size, aiming at size reduction of the automatic transmission 21 for vehicles. Can do.

  In addition, when there are a plurality of embodiments, it is obvious that the characteristic portions of each embodiment can be appropriately combined unless otherwise specified.

DESCRIPTION OF SYMBOLS 1,10,21: Automatic transmission for vehicles, 3: Input direct connection member, 4: Output direct connection member, 5-8: 1st-4th gear connection member, H: Housing, N: Input shaft, T: Output shaft L: rotation axis, CL1: first clutch, CL2: second clutch, CL3: third clutch, B1: first brake, B2: second brake, P1: first planetary mechanism, P2: second planetary mechanism, P3: Third planetary mechanism, P4: Fourth planetary mechanism, S1: First sun gear, S2: Second sun gear, S3: Third sun gear, S4: Fourth sun gear, C1: First carrier, C2: Second carrier, C3: third carrier, C4: fourth carrier, CL4: fourth clutch, R1: first ring gear, R2: second ring gear, R3: third ring gear, R4: fourth phosphorus Gear R4, M: power external take-out member, V1, V2: first and second brake connecting members, U11, U12, U21, U22, U31, U32, U41, U42: first to fourth clutch connecting members

Claims (3)

A housing ;
A second ring gear of the first ring gear and the second planetary gear of the first planetary gear is directly connected to each other, a fourth sun gear of the first ring gear and said second ring gear and the fourth planetary gear is directly connected to the third ring gear of the third planetary gear And a fourth carrier of the fourth planetary gear are directly connected, and four single-pinion planetary gears supported coaxially with the rotation axis on the housing;
An input shaft that is supported by the housing so as to be rotatable about the rotation axis, and is directly connected to the first carrier of the first planetary gear;
Is rotatably journalled on the axis of rotation in the housing and directly output shaft to the fourth carrier,
A first brake for releasably fixing the first sun gear of the first planetary gear to the housing;
A second brake for releasably fixing a fourth ring gear of the fourth planetary gear to the housing;
A first clutch for releasably connecting the first and second ring gears and the fourth sun gear directly connected to each other and the third carrier of the third planetary gear;
A second clutch for releasably connecting the second sun gear of the second planetary gear and the third sun gear of the third planetary gear;
A third clutch for releasably connecting the third carrier and the fourth ring gear;
A fourth clutch for releasably connecting the first carrier and the second carrier of the second planetary gear and the third sun gear which are directly connected to each other;
A vehicle automatic transmission comprising: The first to fourth planetary gears are sequentially arranged in parallel from the input shaft side to the output shaft side in this order,
The first carrier is directly connected to the input direct connection member that is directly connected to the input shaft and passes through the inside of the first sun gear on the output shaft side, and is directly connected to the second carrier and the first and second ring gears. Directly connected to the gear connecting member passing through the outside of the input shaft side,
The fourth clutch is detachably connected to the first and second carriers and the third sun gear via a fourth clutch connecting member directly connected to the gear connecting member.
The automatic transmission for a vehicle according to claim 1, wherein a power external take-out member for taking out power to the outside is provided outside the first and second ring gears in the gear connecting member. The second planetary gear, the first planetary gear, the third planetary gear, and the fourth planetary gear are sequentially arranged in parallel from the input shaft side to the output shaft side in this order,
The second to fourth clutches are arranged on the outer diameter side in the housing,
The second and first carriers are directly connected to the input shaft and directly connected to the input shaft and to the input direct connection member passing through the inside of the second and first sun gears,
The second clutch connects the second sun gear and the third sun gear in a detachable manner via a second clutch connecting member that is directly connected to the third sun gear and passes outside the second and first ring gears. ,
The said 4th clutch connects the said 2nd and 1st carrier and the said 3rd sun gear so that engagement / disengagement is possible via the 4th clutch connection member directly connected with the said 2nd clutch connection member. Automatic transmission for vehicles.

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