JP2897992B2 - Automatic transmission - Google Patents

Description

The present invention relates to an automatic transmission mounted on an automobile, and more particularly, to operating a clutch (for example, a direct clutch) to be engaged during an upshift from an input shaft. The present invention relates to a structure of a cylinder that constitutes a hydraulic actuator to be driven.

(B) Conventional technology Generally, an automatic transmission includes a torque converter and a planetary speed change gear mechanism. The speed change gear mechanism includes an overdrive planetary gear unit as an auxiliary speed change unit, a front planetary gear unit and a rear planetary gear unit. And a main transmission unit.

As shown in FIG. 4, the front planetary gear unit of the main transmission unit includes a carrier 29 directly connected to the output shaft 27 and supporting the planetary pin-on 28, a sun gear 30 fitted on the output shaft 27, and is a ring gear 31 linked via a forward clutch C ₁ on the input shaft 26, also with direct clutch C ₂ is interposed between the input shaft 26 and the sun gear 30, and the sun gear 30 and the casing 7 2nd coast brake B ₁ consisting of a band brake is interposed between, which further 2nd brake B ₂ is disposed consisting of multi-plate via a one-way clutch F ₁ is between the sun gear 30 and the casing 7 I have. The hydraulic actuator 40 for operating the direct clutch C ₂ is disposed member is directly connected to the sun gear 30 side and the hydraulic actuator 39 for operating the forward clutch C ₁ is an input shaft
It is located on the 26 side.

Challenge (c) to be Solved by the Invention Incidentally, in the above-described conventional front planetary gear unit, the input shaft 26 and the hydraulic actuator 40 is the sun gear 30 to engaged and disengaged direct clutch C _2, which is disposed between the sun gear 30 6 (b), for example, at the time of shifting from the second speed to the third speed because it is provided on the member directly connected to the side.
In the lower part the working oil pressure as shown by the solid line direct clutch C ₂ is supplied to the hydraulic actuator 40 shifts the state of the connection, as indicated by a dotted line in FIG. 6 (a), with the sun gear 30 until now The hydraulic actuator 40, which has been stationary, receives the supply of the operating oil pressure, the torque is gradually transmitted from the input shaft 26, and generates a hydraulic pressure based on the centrifugal force therein. increased further connection status direct clutch C ₂ based on, follow the course of increasing the hydraulic force due to the centrifugal force hydraulic actuator 40 is increased further rotation, as shown by hatching in FIG. 6 (b) connection of the direct clutch C ₂ further joined by a centrifugal hydraulic component in hydraulic pressure indicated by a solid line is made extremely rapidly, the output torque as shown in the upper portion of FIG. 6 (b) is indicated by hatching Based on the effect of centrifugal oil pressure,
There is a disadvantage that a shift shock is generated by being rapidly transmitted to the output shaft 27.

In particular, when installing an automatic transmission designed for a high-output and high-torque engine on a vehicle equipped with a relatively low-torque engine, it is appropriate to change the number of friction plates of the clutch and the hydraulic control method only to obtain an appropriate Engagement characteristics could not be obtained, and the overload due to the centrifugal oil pressure had a large effect,
The above-mentioned shift shock is remarkably exhibited.

By the way, the centrifugal oil pressure is determined by the inner and outer diameters of the piston chamber of the cylinder and the rotation speed of the cylinder, and the influence of the outer diameter is particularly large. Therefore, conventionally, for a variety of specifications, a press cylinder is newly designed or a cutting cylinder is used, and the components are changed to adjust the clutch capacity.

Accordingly, the present invention reduces the influence of the centrifugal hydraulic pressure of the hydraulic actuator with minimal changes in parts while keeping the main structure intact, reduces shift shock during gear shifting, and is easy and versatile for various specifications. It is an object of the present invention to provide an automatic transmission that can be used at a low cost.

The present invention according to the means of claim 1 for solving the (d) challenge, a ring gear (31) connecting through the forward clutch input part and (26) (C _1),
A sun gear (30) connected to the input unit via a direct clutch (C ₂ ); and a planetary pinion (28) directly connected to the output unit (27) and meshing with the ring gear (31) and the sun gear (30). A carrier (29) for supporting, the sun gear (S) being stopped at a predetermined gear position based on the connection of the forward clutch (C ₁ ) and the release of the direct clutch (C ₂ ), Based on the connection of the forward clutch (C ₁ ) and the direct clutch (C ₂ ), the sun gear (S) is one step higher than the predetermined shift speed where the sun gear (S) rotates integrally with the input section (26) and the output section (27). in the automatic transmission equipped with a transmission unit to be gear position of the cylinder (44) of the direct clutch hydraulic actuator (40) for operating the (C _2), said via a connecting member (38) Sang (S), an annular sleeve (53) having a predetermined thickness is press-fitted into an inner peripheral surface of an outer diameter side flange portion (44a) of the cylinder, and a piston (51) is slidably contacted with the sleeve. In the shift between the predetermined shift speed and the next higher shift speed,
An automatic transmission characterized in that centrifugal oil pressure acting on the piston (51) is reduced.

According to a second aspect of the present invention, the external friction member (61) of the clutch (C ₂ ) is engaged between the connecting member (38) and the outer diameter side flange portion (44a) of the cylinder. The automatic transmission according to claim 1, wherein the drum-shaped member (54) having a joint portion is integrally fixed.

The present invention according to claim 3 is the automatic transmission according to claim 1 or 2, wherein a check ball (52) for discharging centrifugal hydraulic pressure is arranged near the outer diameter side of the piston (51).

(E) Operation Based on the above configuration, when a predetermined transmission designed for a high-torque engine, for example, is installed in a vehicle equipped with a relatively low-torque engine, main components, for example, a planetary gear unit and the gear While the connecting member (38) and the cylinder (44) whose shapes are defined based on the unit and are integrally fixed to each other are left as they are, an annular sleeve (44) is formed on the inner peripheral surface of the outer diameter side flange portion (44a) of the cylinder. 53).

At a predetermined gear (for example, second speed), the sun gear (S) is in a stopped state, and the cylinder (44) of the hydraulic actuator (40) that operates the direct clutch (C ₂ ) is also in a stopped state. but the direct clutch from this state if (C ₂₎ for supplying hydraulic pressure to the hydraulic actuator (40) up-shifted one stage above the shift stage (e.g., third speed) of the direct by the hydraulic supply clutch (C ₂₎ As the torque capacity increases, the cylinder (44) rotates together with the sun gear (S). At this time, the sun gear (S) and the cylinder (44) move from the stopped state to the input section (26) and the output section (2).
Since the speed is increased by a large amount of rotation change until a relatively high-speed direct rotation that rotates together with 7), the cylinder (44)
Although the amount of change in the centrifugal oil pressure acting on the oil pressure inside the cylinder is large, the annular sleeve (5
According to 3), the outer diameter side of the cylinder (44) is reduced in diameter, and the large change in the centrifugal oil pressure can be reduced accordingly.

On the other hand, when downshifting from the upper gear (for example, the third gear) to the predetermined gear (for example, the second gear), at the start of the gear change, the sun gear rotating with a relatively high-speed direct connection rotation is provided. The hydraulic pressure in the cylinder (44) integrated with (S)
Even if a high centrifugal force acts and the hydraulic pressure to the cylinder is drained, the release of the direct clutch (C ₂ ) tends to be delayed due to the residual hydraulic pressure due to the centrifugal force. And the oil pressure in the cylinder (44) is released quickly.

In particular, when the check ball (52) for discharging the centrifugal hydraulic pressure is arranged on the piston (51), the position of the check ball is on the inner diameter side by the thickness of the annular sleeve (44), and the acting centrifugal hydraulic pressure is also lower than the ball. To reduce the centrifugal force acting on
The adjustment of the check ball becomes easy and the cylinder (4
4) When the hydraulic pressure is supplied to the inside, the ball is securely closed, and when the drain is drained, the ball is immediately released to reliably and accurately supply and discharge the hydraulic pressure regardless of the sudden change in the rotational speed.

The reference numerals in the parentheses are for comparison with the drawings, but do not limit the configuration of the present invention.

(F) Example Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIG. 3, the automatic transmission 1 includes a torque converter 2, a planetary transmission gear mechanism 3, and a hydraulic control mechanism 5.
Which are housed in the converter housing 6, the transmission case 7, the valve body 10 and the oil pan 11, respectively. The torque converter 2 includes a lock-up clutch 12, and transmits the rotation of the input member 13 to the input shaft 15 of the transmission gear mechanism 3 via the oil flow of the torque converter 2 or directly by the lock-up clutch 12. The transmission gear mechanism 3 is a main transmission unit including an overdrive planetary gear unit 17, a front planetary gear unit 19 and a rear planetary gear unit 20.
It consists of 21. Overdrive planetary gear unit
Reference numeral 17 denotes a carrier 24 directly connected to the input shaft 15 and supporting the planetary pinion 22, a sun gear 23 fitted on the input shaft 15, and a ring gear connected to an input shaft 26 serving as an input portion of the main transmission unit 21. has a 25, also with overdrive direct clutch C ₀ and the one-way clutch F ₀ is interposed between the planetary carrier 24 and the sun gear 23, the overdrive frame key B ₀ between the sun gear 23 and the case 7 Are arranged.

Further, the front planetary gear unit 19 is directly connected to the output shaft 27 serving as an output portion and supports the planetary pinion 28, is fitted to the output shaft 27, and is integrally formed with the sun gear 30b of the rear planetary gear unit 20. Sun gear 30a and forward clutch C
_The ring gear 31 is connected to the input shaft 26 and the sun gear 30. A direct clutch C2 is interposed between the input shaft 26 and the sun gear 30, and a _second brake is provided between the sun gear 30 and the case 7. Coast and brake B ₁ is interposed is further 2nd brake B ₂ is disposed consisting of multi-plate via a one-way clutch F ₁ between the sun gear 30 and the case 7.

The rear planetary gear unit 20 includes a carrier 33 supporting the planetary pinion 32, a sun gear 30b, and a ring gear 35 directly connected to the output shaft 27. A 1st & Rev brake B ₃ and a carrier ₃ are provided between the carrier 33 and the case 7. the one-way clutch F ₂ are arranged in parallel.

Further, the input shaft 26 of the front planetary gear unit 19
An enlarged diameter portion 26a is formed in the vicinity of the rear end portion, and an annular flange portion 37 is fixed to the enlarged diameter portion 26a, and the flange portion 37 and the enlarged diameter portion 26a near the rear end portion of the input shaft are combined. Forward clutch C
The cylinder of the _first hydraulic actuator 39 is configured.
The annular flange 37 extends in the axial direction and has splines formed on its inner peripheral surface, respectively. The spline formed between the inner peripheral spline of the annular flange 37 and the outer periphery of the axially extended portion of the ring gear 31 is formed. Has a forward clutch
Numerous outer and inner friction plates which constitute the C ₁ is fit retaining at snap ring with which engaged respectively engaged alternately.
Then, the flange portion 37 and the rear end outer periphery 26a of the input shaft 26 are formed.
The piston for the hydraulic actuator 39, which is formed by an O-ring, is oil-tightly fitted with an O-ring, and a return spring is compressed between the cylinder and the plate fixed to the outer periphery 26a of the rear end of the input shaft. Has been established.

On the other hand, a sleeve 27a is rotatably supported on the output shaft 27, and a flange-like member 38 constituting a connecting member is fixed to the sleeve 27a. The flange-like member 38 extends the outer so as to surround the forward clutch C ₁ in the axial direction, and the tip portion thereof, an annular flange 44 which is rotatably sliding contact with the input shaft 26 is fixed .
As shown in detail in FIG. 1, a drum-shaped member 54 is interposed and fixed between the flange member 38 and the annular flange 44. The drum-shaped member 54 is cut into a comb-like shape. , notch constitutes the engaging portion which engages the outer friction plates 61 for the direct clutch C _2. Further, the inner diameter side of the outer friction plate 61 protrudes a hub 59 fixed to the input shaft 26 with an annular flange 37 constituting the forward clutch C ₁ of the cylinder, cut into dentate of the hub portion 59 Dr. away in it, the cutout constitutes an engaging portion for engaging the inner friction plate 60 for the direct clutch C _2.

Further, since the inner peripheral surface of the annular flange 44 and constitute the normal cylinder for direct clutch C _2, in this embodiment, to meet the low torque for the engine, the flange
An annular sleeve 53 having a predetermined thickness is press-fitted on the inner peripheral surface of the outer diameter side flange portion 44a of 44, and a piston is provided between the sleeve 53 and the outer peripheral surface of the inner diameter side flange portion 44b of the annular flange 44. 51
Are oil-tightly fitted by O-rings 55 and 56. Further, a check ball 52 is provided on the piston 51 in the vicinity of the piston outer diameter side O-ring 55, and the check ball 52 allows centrifugal drainage to escape. A plate 57 is fixed to the inner flange portion 44b of the annular flange 44, and a spring 58 is contracted between the plate 57 and the piston 51.

In another embodiment, a groove for the O-ring 55 is formed in the sleeve 53, as shown in FIG. The other components are the same as those shown in FIG. 1, and the description is omitted. According to this embodiment, the check ball 52 can be disposed on the outermost diameter side of the piston 51, and the centrifugal oil can be reliably discharged.

 Next, the operation of the present embodiment will be described.

Each clutch C ₀ , C ₁ , C ₂ and brake of the automatic transmission 1
B ₀ , B ₁ , B ₃ and each one-way clutch F ₀ , F ₁ , F ₂ are:
The gears at the respective positions P, R, R (V ≧ 7), N, D, 2, and L are controlled as shown in the operation table of FIG.

That is, at the 1st speed in D range or 2 range, O / D
The direct clutch C ₀ , the one-way clutches F ₀ and F _2, and the forward clutch C ₁ are engaged, and the others are in the released state. Therefore, O / D planetary gear unit 17 has a directly coupled together via the clutch C ₀ and the one-way clutch F _0, the rotation of the input shaft 15 is transmitted directly to the input shaft 26 of the main transmission unit 21 You. In the main transmission unit 21, the rotation of the input shaft 26 is controlled by the forward clutch C _1.
Through the ring gear 31 of the front planetary gear unit 19, and further to the carrier 29 and the output shaft 27 integral with the carrier 29, and the leftward rotation of the carrier 33 of the rear planetary gear unit 20 through the sun gear 30. The rotation is prevented by the one-way clutch F ₂ , and the planetary pinion 32 rotates by itself to rotate the output shaft 27.
The power is transmitted to the ring gear 35 integral with the ring gear 35.

In the 2nd speed in the D range, the O / D direct clutch C ₀ , the one-way clutch F ₀ , the forward clutch
C ₁ , the one-way clutch F ₁ and the second brake B ₂ are engaged, and the others are in the released state. Therefore, the O / D planetary gear unit 17 is in the directly connected state described above, and the rotation of the input shaft 15 is transmitted to the input shaft 26 of the main transmission unit 21 as it is. The main speed change unit 21 is transmitted to the ring gear 31 of the front gear unit 19 the rotation of the input shaft 26 through the forward clutch C _1, imparts a rotational force of the left direction to the sun gear 30 through the pinion 28, the The sun gear 30 is prevented from rotating in this direction by the one-way clutch F ₁ associated with the engagement of the _second brake B ₂ , so that the planetary pinion 28 rotates while the carrier 29 rotates, and the sun gear 30 rotates only through the front gear unit 19. The high speed rotation is transmitted to the output shaft 27.

Incidentally, the hydraulic actuator to engaged and disengaged direct clutch C ₂ disposed between the input shaft 26 and the sun gear 30
40 is provided on a member directly connected to the sun gear 30, the hydraulic actuator 40 is provided at the above-described second speed.
Is stationary with the sun gear 30.

Then, when shifting from the second speed to the third speed, when working oil pressure as shown by the solid line in the lower portion of FIG. 6 (b) is supplied to the hydraulic actuator 40 is a direct clutch C ₂ shifts to the connected state, As shown by the dotted line in FIG.
The hydraulic actuator 40 which has been stationary with the sun gear 30 receives the supply of the operating hydraulic pressure, the rotational force is gradually transmitted from the input shaft 26, and generates a hydraulic pressure based on the centrifugal force therein. following the course of increasing the hydraulic force due to the centrifugal force by increasing the rotating hydraulic actuator 40 is further increased further connected state direct clutch C ₂ on the basis of the hydraulic pressure supplied, further centrifugal hydraulic matter the working oil pressure In addition, since the pressure receiving area on the outer diameter side of the piston is reduced, the centrifugal oil pressure can be greatly reduced, and the shift shock can be reduced.

Also, at 3rd speed in D range and 2 range, O / D
The direct clutch C ₀ , the one-way clutch F _O , the forward clutch C ₁ , the direct clutch C ₂ and the second brake B ₂ are engaged, and the others are in the released state. Accordingly, the O / D planetary gear unit 17 is in the directly connected state described above, and the main transmission unit 21 is configured such that the front planetary gear unit 19 is integrated with the two clutches C ₁ and C ₂ to form the input shaft 26. The rotation is transmitted to the output shaft 27 as it is.

At the fourth speed in the D range, that is, at the highest speed, the forward clutch C ₁ , the direct clutch C ₂ and the second brake B ₂ are in the engaged state, and the main transmission unit 21 is in the directly connected state as in the case of the third speed. , the overdrive planetary gear unit 17, the brake B ₀ is switched to engage with the direct clutch C ₀ is released. Therefore, the sun gear 23 is locked by the brake B _0, the carrier
While the 24 rotates, the planetary pinion 22 rotates and transmits power to the ring gear 25, and the speed-up rotation (overdrive)
Is transmitted to the input shaft 26 of the main transmission unit 21 in the directly connected state.

Further, when the second speed in the 2nd range and 1 range, 2nd coast brake B ₁ is engaged than the second speed when the D-range, lock the sun gear 30 of the main transmission unit 21,
Apply engine brake.

Also, 1 case 1 speed in the range, 1st & Rev brake B ₃ than the first speed in the D-range is engaged, to lock the carrier 33 of the rear planetary gear unit 20, Kikaseru engine braking.

In the R range, the O / D direct clutch C ₀ , the one-way clutch F _O , the direct clutch C ₂ and the brake B ₃ are engaged, and the others are in the released state. Therefore, O / D planetary gear unit 17 is in a directly connected state, also the main transmission unit 21, rotation of the input shaft 26 is transmitted directly to the sun gear 30 by the clutch C _2, and the rotation of Riakyariya 33 is locked by the brake B ₃ Therefore, the rotation of the sun gear 30 is transmitted as reverse rotation to the ring gear 35 via the rotation of the planetary pinion 32, and reverses the output shaft 27.

Further, while the vehicle is running in the forward direction at a predetermined speed for example 7km / H or more, when shifting the shift lever to the R range, 1st & Rev brake B ₃ releases with direct clutch C ₀ is released. This state is similar to the state at the time of parking P and the time of neutral N, and the main transmission unit
21 is in a free state to prevent the gear from being damaged.

(G) Effects of the Invention As described above, according to the present invention, since the annular sleeve having a predetermined thickness is press-fitted on the inner peripheral surface of the cylinder outer diameter side flange portion of the hydraulic actuator for operating the direct clutch, However, despite the rapid change in rotation between the stop state and the relatively high-speed rotation that rotates integrally with the input unit and the output unit, the amount of change in the centrifugal oil pressure acting in the cylinder by the sleeve is reduced. Thus, the direct clutch can be smoothly engaged or disengaged, and the shift shock between the predetermined shift speed and the immediately higher shift speed can be reduced.

As a result, it is possible to reduce the pressure receiving area on the outer diameter side of the piston by changing the minimum parts while keeping the main parts intact.For example, an automatic transmission designed for a high-output and high-torque engine can be relatively manufactured. Even if it is installed in a vehicle with a low-torque engine installed, the shift shock can be reduced as described above, thereby making it possible to easily and inexpensively match the characteristics of the automatic transmission with various specifications. Can be.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a hydraulic actuator of a (direct) clutch according to the present invention, and FIG. 2 is a view showing another embodiment. FIG. 3 is an overall sectional view of the automatic transmission applied to the present invention, FIG. 4 is a schematic diagram of a main part of the automatic transmission applied to the present invention, and FIG. 5 is an operation table thereof. . FIG. 6 shows the shift characteristics of a conventional automatic transmission, wherein (a) shows the rotational characteristics of each part, and (b) shows the output rotational torque and hydraulic characteristics. DESCRIPTION OF SYMBOLS 1 ... Automatic transmission, 19 ... Transmission unit (front planetary gear unit), 26 ... Input part (shaft), 27 ... Output part (shaft), 28 ... Pinion, 29 ... Carrier, 30 ... Sun gear,
31… Ring gear, 38… Connecting member (flange member), 40…
Hydraulic actuator, 44 ... cylinder (annular flange),
44a ... outer diameter side collar portion, 51 ... piston, 52 ... check ball, 53 ... sleeve, 54 ... drum-shaped member, 55, 56 ... O-ring, 61 ... outer friction member, C ₁ ... forward clutch, C ₂ ... Direct clutch.

──────────────────────────────────────────────────の Continued on the front page (72) Kunihiro Iwazuki, Toyota Town, Toyota, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Yoshiharu Harada, Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Yasushi Ando 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (56) References JP-A-62-72930 (JP, A) JP-A-62-181725 (JP, U) 1975-35085 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 61/26-63/38 F16D 25/063

Claims (3)

(57) [Claims] 1. A ring gear connected to an input unit via a forward clutch, a sun gear connected to the input unit via a direct clutch, and a planetary pinion directly connected to an output unit and meshing with the ring gear and the sun gear. The sun gear is in a stopped state at a predetermined gear position based on the connection of the forward clutch and the release of the direct clutch, and the sun gear is in the stopped state based on the connection of the forward clutch and the direct clutch. In an automatic transmission including a transmission unit that is one step higher than the predetermined gear that rotates integrally with an input unit and an output unit, a cylinder of a hydraulic actuator that operates the direct clutch includes a coupling member via a connecting member. Connected to a sun gear, and An annular sleeve having a predetermined thickness is press-fitted on the surface, and a piston is slid on the sleeve to reduce the centrifugal hydraulic pressure acting on the piston during the shift between the predetermined shift speed and the next higher shift speed. Automatic transmission characterized by the following. 2. A drum-shaped member having an engaging portion with which an external friction material of the clutch is engaged is integrally fixed between the connecting member and an outer diameter side flange portion of the cylinder. 1. The automatic transmission according to 1. 3. The automatic transmission according to claim 1, wherein a check ball for centrifugal hydraulic pressure discharge is arranged near an outer diameter side of the piston.