JPS59179423A - Transmission for vehicle - Google Patents

Abstract

PURPOSE:To make a mechanism into simplification and lightweightness as well as to aim at improvements in a rate of fuel consumption, by coupling a planetary gear transmission mechanism and a planetary gear shaft different in a transmission ratio each, together in common in series, while making one of internal gears brakable selectively by means of liquid pressure. CONSTITUTION:One of braking devices 11a-11c of a multistep transmission mechanism A is selectively operated, while one of braking devices 12a-12b of a multistep transmission mechanism B is as well operated, and when each internal gear is set in brake motion, power of an input shaft 1 is gear-shifted and transmitted to an output shaft 2 via a planetary gear transmission mechanism corresponding to the brake motion of these internal gears. When the braking device is changed over, the transmission of power in another transmission ratio takes place via another planetary gear transmission, that is to say, a 6-step transmission is performable owing to the gearshift of 3-step speed at the S side and 2-step speed at the B side. In addition, when one side of these braking devices 12a and 12b of a reverser mechanism C is operated, power of the input shaft 1 is shifted to 2-step speed and reversely transmitted to the output shaft 2. With this, improvements in lightweightness and fuel consumption can be well promoted as a compactified transmission mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission for a vehicle.

Vehicles such as large trunks, heavy-duty tractors, and sports cars are equipped with transmissions that have an extremely large number of gears in order to draw engine output to the drive wheels with high efficiency. However, such a transmission with a large number of gears has a complicated and heavy mechanism, which causes a problem of lowering the fuel consumption rate of the engine.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, an object of the present invention is to provide a vehicular transmission that is a multi-speed transmission, but has a simplified and compact mechanism, is lightweight, and can reduce the fuel consumption rate of the engine. It is to do so.

A vehicular transmission according to the present invention that achieves the above object connects an input shaft and an output shaft with a multi-stage transmission mechanism in which planetary gear transmission mechanisms with different gear ratios are connected in series, and The multiple planetary gears in the transmission mechanism are pivotally supported on a common planetary gear shaft, the multiple sun gears are similarly fixed on the common sun gear shaft, and the multiple internal gears are free without being pivotally supported. It is characterized in that it is loosely fitted into the housing case, and one of the internal gears can be selectively braked by a fluid pressure braking means.

The present invention will be explained below with reference to embodiments shown in the drawings.

In the examples, those shown in FIGS. 1 and 6 have a total reduction ratio of 1.
: 1, which has 6 forward speeds and 2 reverse speeds, and except for the reverse (reverse) mechanism, a multi-stage reduction mechanism and a multi-stage speed increase mechanism are connected in series. In order to further increase the total reduction ratio, the multi-stage reduction mechanism may be connected in series in more stages. Also, what is shown in Fig. 7 is the case of 6 forward speeds and 2 reverse speeds, in which two groups of multi-stage reduction mechanisms are connected in series, so that the total reduction ratio can be made larger than around 1:1. This is what I did. In any of the above cases,
If it is desired to further increase the number of gears, the number of gears of the multi-stage transmission mechanism may be increased, or another multi-stage transmission mechanism may be added in series.

In the embodiment shown in FIG. 1, ] is an input shaft, and 2 is an output shaft. Input shaft 1 is directly connected to the engine crankshaft, or
Alternatively, engine power is input via the fluid coupling 3 shown in phantom lines). Further, the output shaft 2 outputs power to a drive wheel (not shown).

Between the input shaft 1 and the output shaft 2, multi-stage transmission mechanisms A and B consisting of a planetary gear transmission mechanism are connected in series,
Further, on the input shaft 1 side, a reversing mechanism C of a planetary gear mechanism connected to these multi-stage transmission mechanisms A and B is provided.

Three sun gears 4a, 4b, 4c constituting the multi-stage transmission mechanism A are fixed in series to the shaft end of the input shaft 1, and each of these sun gears 4a, 4b, 4c has a planetary gear 7a.
, 7b and 7c mesh, and this planetary gear? a, 7b, 7c
Internal gears 8a, 8b, and 8c mesh with each other to form a three-stage planetary gear reduction mechanism with different speed ratios. The sun gears 4a, 4b, and 4c are fixed to the input shaft 1 as a common sun gear shaft. Further, two sun gears 6a and 6b constituting the multi-stage transmission mechanism B are fixed to the shaft end of the output shaft 2, and planetary gears 9a and 9bf) mesh with these sun gears 5a and 5b, respectively. The internal gears 10a and 10b mesh with the planetary gears 9a and 9b, forming a two-stage planetary gear speed increasing mechanism with different gear ratios.

The sun gears 6a, 6'b have the output shaft 2 as a common sun gear shaft. Each internal gear 8a, 8b.

They are provided on the housing case 13 side, facing 8C and 10a, 10b, respectively.

These braking means selectively brake one of the internal gears in the multi-stage transmission mechanism A and one of the internal gears in the multi-stage transmission mechanism B using hydraulic pressure.

The plurality of planetary gears 7a, 7b, 7c and 9a, 9b
are simultaneously rotatably supported on a common planetary gear shaft 14. This planetary gear shaft 14 consists of two carriers 15 and 16 that are pivotally supported by the housing case 13, and one carrier '+17 that is pivotally supported at a position where the shaft end of the input shaft 1 and the shaft end of the output shaft 2 meet. It is supported by.

In addition, the gears 8a and 8 are connected to the multi-stage transmission mechanism A and B.
b, 8c, 10a, and 10b are not particularly supported by a support mechanism other than being meshed with the planetary gear, and are loosely fitted inside the housing case 13.

On the other hand, a sun gear 5 constituting a reversing mechanism C is fixed to the middle of the input shaft 1. This sun gear 5 has a planetary gear 1
8 meshes well, and the internal gear 1 meshes with this planetary gear weight 8 to form a planetary gear reduction mechanism. The internal gear 19
is 2. At the same time, it is spline connected to the boss portion of the carrier 15. The planetary gear 18 is connected to the carrier shaft 21 of the carrier 20.
The carrier 20 is rotatably supported by a shaft, and the carrier 20 can be braked by a hydraulically actuated brake means 22 provided inside the housing case 13. This braking means 22 has the same structure as the braking means for braking the internal gear described above.

2 and 3 are representative illustrations of the above-mentioned hydraulically operated braking means 11a, and the other braking means have the same construction.

In FIGS. 2 and 3, a ring-shaped cylinder 23 is provided inside the housing case 13 and has an open inner periphery over the entire inner periphery so as to face the internal gear 8a. Similarly, a ring-shaped piston 24 is loosely fitted into the ring. A keyway 2 is provided on the outer surface of the piston 24.
A key 28 fixed to the cylinder 23 side is fitted into the key a27 to guide the piston 24 along the longitudinal direction of the key 28 and prevent it from rotating.

Three friction plates 30 are provided between the tip of the piston 24 and the wall surface 13a of the housing case 13 facing the tip
31.32 are intervening.

Of these, the friction plate 30 is slidably engaged with the teeth on the outer circumferential side of the internal gear 8a in the axial direction, and the friction plate 32 is press-fitted and fixed to the teeth on the outer circumferential side of the internal gear 8a. Friction plate 3
1 is located between the friction plates 30 and 32, engages with the key 28, and is loosely fitted so as to be movable in the axial direction.

The inside of the piston 24 has a hollow shape,
A bellows 25 is installed inside the cavity. 'This bellows 25 connects a pipe plug 29 protruding from the rear surface to the hydraulic pressure supply path 26, and is expanded by the supplied pressure oil.
The piston 24 is connected to the wall surface 13a of the housing case 13.
By pressing toward the friction plates 30, 31, 32
Press down. By the pressing operation of this friction plate, the internal gear 8a
is braked. Also, if the hydraulic pressure is released, the bellows 25
is restored by its own elastic force, so the internal gear 8a becomes free.

As shown in FIGS. 4 and 5, the bellows 25 has a plurality of ring-shaped partition plates 33 separated from each other at predetermined intervals, and the outer and inner peripheries of adjacent ring-shaped partition plates 33 and 33 are separated from each other by a predetermined interval. They are connected by a thin film 34 made of elastic steel or the like, and the inside thereof is formed into a plurality of pressure chambers 35 that communicate with each other. With this configuration, the ring-shaped partition plate 33 having high rigidity prevents the thin film 33 from expanding in the radial direction when hydraulic pressure is applied, thereby preventing the thin film 33 from bursting.

In the transmission described above, braking means 11a and 11b are compatible with the multi-stage transmission mechanism.

11c and selectively activates or moves one of the braking means 12a, 12b corresponding to the multi-stage transmission mechanism B to brake each internal gear. Power from the input shaft 1 is transmitted to the output shaft 2 via a planetary gear transmission mechanism corresponding to the gears. When the braking means is switched, power is transmitted at a different speed ratio via another planetary gear transmission mechanism. That is, in this transmission, a total of 3×2=6 speeds can be changed by 3 speeds on the side of the multi-speed change mechanism A and 2 speeds on the side of the multi-speed change mechanism B. Further, when the braking means 22 of the reversing mechanism C is activated and either the braking means L2a, L2b of the multi-stage transmission mechanism B is actuated, the power of the input shaft 1 is transferred to the output shaft 2.
The signal is switched to the second stage and the reverse transmission is transmitted.

The number of stages of the multi-stage transmission mechanism A and the multi-stage transmission mechanism B can be set to any number as necessary.

The selection operation of the braking means in the multi-stage transmission mechanism AI and reversing mechanism C on the input shaft 1 side and the selection operation of the braking means in the multi-stage transmission mechanism B on the output shaft 2 side can be performed manually, but as shown in FIG. It is even more convenient to perform the process automatically as shown in the figure below.

In FIG. 6, each of the above-mentioned braking means 11a.

11b, llc, 1.2a, 12b, and 22 are connected to a hydraulic pressure supply source 41 via a solenoid valve box 40.

Each solenoid valve in the solenoid valve box 40 opens and closes under the control of a command signal from the controller 42, and hydraulic pressure is supplied only to the braking means corresponding to the opened solenoid valve.

On the other hand, the input shaft 1 is provided with a detector 43 that detects its rotational speed, torque, etc., and a detection signal from this detector 43 is input to the controller 42. The controller 42 includes an analog-to-digital converter 44. Microcombi j1. -ta45. A switch box 46 is provided, and the detection signal of the detector 43 is A/D converted by an analog/digital converter 44, and then processed by a microcomputer 45. microcomputer 45
calculates the gear ratio that maximizes the engine output at that time in accordance with the rotational speed or torque of the input shaft 1, and controls the braking means on the side of the multi-stage transmission mechanism A to achieve the calculated gear ratio. A command is issued to the switch hook 46 to select one of the braking means on the side of the multi-stage transmission mechanism B, and the corresponding solenoid valve in the solenoid valve box 40 is opened in accordance with the signal. Furthermore, when moving backward, a signal for selecting one of the braking means 22 of the reversing mechanism C and the braking means of the multi-stage transmission mechanism B is commanded to the solenoid valve box 40 via the switch box 46 as well.

In the above, the detector 4 detects the rotation speed or torque, etc.
3 may be provided on the output shaft 2 side. Furthermore, in the case of manual operation instead of automatic control, the solenoid valve box 40 may be operated manually.

In the above embodiment, the multi-stage transmission mechanism A is a planetary gear reduction mechanism, and the multi-stage transmission mechanism B is a planetary gear speed increase mechanism.
As shown in FIG. 7, the multi-stage transmission mechanism B may be replaced with a multi-stage transmission mechanism B' consisting of the same planetary gear reduction mechanism as A. That is, sun gears 6a' and '6b' fixed to a common sun gear shaft 70, planetary gears 9a' and 9b'' that mesh with the sun gears, and an internal gear 10a' that meshes with the sun gears.
, 10b'', and each internal gear 10a'.

10b° corresponds to hydraulic braking means 12a', 12b'.

In the case of FIG. 7, the gear ratio can be made larger than in the case of FIG. 6, as described above.

According to the transmission described above, for forward shifting, the number of gears is the product of the number of gears of the multi-stage transmission mechanism A on the input shaft example and the number of stages of the multi-stage transmission mechanism B on the output shaft 2 side, and for reverse gearing, the number of gears is the product of the number of gears of the multi-stage transmission mechanism B on the output shaft 2 side. The number of gears is multiplied by the number of gears of the multi-stage transmission mechanism B, so it is possible to perform extremely multi-stage shifting in both forward and reverse directions. Further, this number of gears can be set to any desired number of gears by adding an extra multi-stage transmission mechanism in series with the number of stages of the multi-stage transmission mechanism. Furthermore, it is preferable that the multi-stage transmission mechanism has two or more groups such as A and B, but it is also possible to provide only one group.

In such a multi-stage transmission, the sun gears 4a, 4b, 4c of the multi-stage transmission mechanism A are fixed to a common sun gear shaft consisting of the input shaft 1, and the sun gear 6a of the multi-stage transmission mechanism B,
, 6b are also fixed to a common sun gear shaft consisting of the output shaft 2, and the planetary gears 7a, 7b, 7c of the multi-stage transmission mechanisms A, B
, 9a, 9b are similarly supported by a common planetary gear shaft 14. Furthermore, internal gears 8a, 8b, 8c, 10a,
10b is not pivotally supported by a support mechanism (it has a structure in which it is loosely fitted into the hekeging case 13 in a free state. Therefore, a very large number of gears are not supported by a support mechanism, but it is necessary to commonize and omit these support mechanisms. This simplifies the support mechanism and reduces the space that these support mechanisms would normally occupy.As a result, the entire device is made more compact.
The weight is significantly reduced and the fuel consumption rate of the vehicle engine can be reduced.

Further, according to the configuration of the above embodiment, since the bellows 25 is used to drive the piston 24 of the braking means, the gap between the cylinder and piston is similar to the relationship between the cylinder and the piston in a conventional hydraulic system. Since the curve does not curve, an extremely small-capacity device is required as a hydraulic pressure supply source. Further, accordingly, highly efficient operation with little loss can be performed, and the pressurization speed of the piston 24 can be adjusted extremely easily.

Furthermore, if the piston 24 is formed into a hollow structure and the bellows 25 is disposed inside the hollow structure as in the embodiment, the space occupied by the bellows 25 is reduced, and the device can be made more compact. can be made advantageous.

Furthermore, since the bellows 25 itself has an elastic recovery force, it automatically returns to its original position by contraction after the hydraulic pressure is released. Therefore, it is not necessary to provide a special return spring mechanism to return the piston 24 to its original position.

In the transmission described above, a fluid coupling may be provided between the engine and the hydraulic braking means using the bellows, but unlike conventional hydraulic mechanisms, there is no oil leakage, so hydraulic control can be performed accurately. Therefore, it is also possible to omit this fluid coupling.

The transmission of the present invention is applicable to trucks.

It can be effectively used in vehicles such as buses, tractors, and passenger cars. In particular, it is extremely effective for vehicles that require a large number of gears.

As described above, the vehicular transmission of the present invention connects the input shaft and the output shaft with a multi-stage transmission mechanism in which planetary gear transmission mechanisms with different gear ratios are connected in series. Multi-stage transmission mechanism The middle number of planetary gears are pivotally supported on a common planetary gear shaft, multiple sun gears are similarly fixed on a common sun gear shaft, and multiple internal gears are free without being pivotally supported. In this way, one of the internal gears can be selectively braked by a fluid pressure braking means, so that a multi-stage transmission mechanism consisting of a planetary gear mechanism can be set up between a sun gear group and a planetary gear group. By sharing the support mechanism with each group and omitting the support mechanism of the internal gear, the overall mechanism becomes simpler, more compact, and lighter. As a result, the fuel consumption rate of the engine can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a transmission according to the present invention, Fig. 2 is a longitudinal sectional view of the main parts of the transmission, Fig. 3 is a sectional view taken along the line mm in Fig. 2, and Fig. 4 is the same. FIG. 5 is a longitudinal cross-sectional view of a bellows used in the braking means of the transmission, FIG. 5 is a cross-sectional view along the line V-V in FIG. 4, FIG. 6 is a circuit diagram for automatic control of the transmission, and FIG. FIG. 3 is a schematic diagram of a transmission according to another embodiment. 1...Input shaft, 2...Output shaft, 4a, 4b, 4c,
6a, 6b - sun gear, 7a. 7b, 7C, 9a, 9b--planetary gear, 8a, 8b,
8c, 10a, 10b-・Internal gear, lla, llb
, llc, 12a, 12b... Braking means, 13... Housing case, 23... Cylinder, 24... Piston, 25... Bellows, A, B... Multi-stage transmission mechanism. Agent Patent Attorney Shin Ogawa - Patent Attorney Ken Noguchi Teru Patent Attorney Kazuhiko Saishita Figure 2 Figure 3

Claims (1)

[Scope of Claims] (11 A multi-stage transmission mechanism formed by serially connecting a planetary gear transmission mechanism with a transmission ratio of 2 is interposed between the input shaft and the output shaft, A plurality of planetary gears are pivotally supported on a common planetary gear shaft, a plurality of sun gears are similarly fixed on a common sun gear shaft, and a plurality of internal gears are placed freely in a housing case without being pivotally supported. A vehicular transmission characterized in that the internal gears are loosely fitted and one of the internal gears can be selectively braked by a fluid pressure braking means. (2) A plurality of groups of multi-stage transmission mechanisms are connected in series, and each A vehicular transmission according to claim 1, wherein one of the internal gears in the multi-stage transmission mechanism can be selectively braked by a fluid pressure braking means. A braking means is constituted by a ring-shaped cylinder provided with a ring-shaped cylinder, a ring-shaped piston loosely fitted into the cylinder, and a bellows interposed at the rear of the piston, and the bellows is expanded by fluid pressure to drive the piston. and a vehicle transmission according to claim 1 or 2, which brakes the internal gear. (4) A detector is provided to detect the rotational speed or torque of the input shaft or the output shaft, A vehicle according to claim 1, 2, or 3, wherein one of the internal gears in the multi-speed transmission mechanism is selectively and automatically braked by the controller based on the detection signal of the detector. transmission.