JPH0546453B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention is useful for climbing steep slopes, such as in a four-wheel drive vehicle, for example.
Regarding transmissions of vehicles capable of driving on rough roads, etc.
In particular, the Emergent Low (hereinafter abbreviated as EL) gear, which has a larger gear ratio than 1st gear, is assembled in a two-shaft, constantly meshing structure, similar to each forward gear. Regarding.

[Conventional technology]

Four-wheel drive vehicles have double the tire grip power compared to two-wheel drive vehicles, and are superior in climbing hills and on rough roads. The applicant has already proposed adding an EL gear with a gear ratio larger than the first gear to each gear, and using this EL gear to improve driving performance on steep climbs, etc. Here, in a transmission with 4 forward gears and 1 reverse gear, the shift position opposite to the reverse gear is open, and when escaping from a rough road, the shift position is the same as the reverse gear. on the opposite side of the direction
It is desirable to have an EL gear. Also, in terms of production,
In terms of compatibility with other car models, it is desirable to have an EL gear gear mechanism separate from the gear mechanism that obtains the normal 1st to 4th gears.For this reason, the reverse gear group , the gear mechanism consisting of the gear group of the EL gear stage and the synchronization mechanism that selects one of them is configured separately with the same two-shaft constant meshing type as the gear mechanism of the forward speed of the first to fourth speeds. . By the way, it is composed of two shafts that are constantly in mesh.
In the gear group of the EL conversion stage, the distance between the EL drive gear on the main shaft side and the EL driven gear on the subshaft side is fixed, and even when reducing the number of teeth on the EL drive gear to increase the gear ratio, the distance between the shafts is fixed. Since there is a limit to this, there is a problem in that it is difficult to set a large gear ratio for the EL gear stage, and it becomes impossible to set a gear ratio higher than a certain level. Therefore, in order to set a large gear ratio for the EL gear stage, it is not only necessary to reduce the speed by one stage using the above-mentioned set of EL drive and driven gear, but also to incorporate other deceleration gears in between to perform multi-stage deceleration. Good. In this case, the configuration of the gear group of the EL conversion stage is such that the first stage deceleration is performed by transmitting the information from the EL drive gear on the main shaft to the idler driven gear on the intermediate shaft, and then from the idler drive gear integrated with the idler driven gear to the idler driven gear on the intermediate shaft. It is transmitted to the large-diameter driven gear of the countershaft via the intermediate gear provided on the intermediate shaft.
It is known that the gears are arranged on four axes by decelerating each stage. As a prior art related to this point, for example, there is a publication published in Japanese Patent Application Laid-Open No. 56-90156.

[Problem to be solved by the invention]

However, in the above publication, there is an idler gear shaft that decelerates and extracts the power from the main shaft, and the gear shaft has an idler gear and a second stage reduction gear, and the power is transmitted from the idler drive gear to the subshaft via an intermediate gear. It has a structure that meshes directly with the driven gear, and the intermediate shaft is not used for deceleration. Also,
Since the intermediate gear that meshes with the speed reduction gear of the gear shaft and serves both for speed reduction and rotational direction conversion is independently supported, the structure is complicated and additional space is required. Furthermore, since the gear itself is directly meshed with the gear of the subshaft, there is a lack of freedom in selecting the gear ratios of the second and third stages before and after the gear that serves both for speed reduction and rotational direction conversion. The present invention was made in view of the above circumstances, and it is possible to manufacture the transmission at a low cost by configuring the gear shaft of the transmission with three basic shafts: a main shaft, a counter shaft, and a reverse idler gear shaft. Moreover,
It is an object of the present invention to provide a vehicle transmission that has three EL reduction stages and allows the gear ratio to be arbitrarily set to a large value.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a gear mechanism that obtains an emergent low gear ratio that is larger than reverse gear and first gear, by meshing the idler gear of the idler gear shaft with the reverse gear drive gear of the main shaft. The first stage of deceleration is performed, and the second stage of deceleration is performed by meshing the drive gear of the idler gear shaft with the driven gear of the intermediate gear that serves both deceleration and rotational direction conversion on the main shaft. 3 by engaging the driven gear of the shaft.
A gear group for the emergent low conversion stage is configured to reduce the speed of the stage, and the driven gear is integrated with the secondary shaft by the synchronization mechanism of the countershaft to obtain the emergent low gear stage, and the gear group is formed in the synchronization mechanism. The invention is characterized in that the reverse gear driven gear is meshed with the idler gear to obtain the reverse gear.

【Example】

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. 1 and 2, the case of a four-wheel drive vehicle will be explained as an example to which the present invention is applied. Reference numeral 1 denotes a clutch, and this clutch 1 is connected to the front and rear through the transmission 2 according to the present invention. Direct transmission is configured to the final reduction device 3 on one side of the wheel, and the final reduction device 3
Furthermore, the structure is such that power is transmitted to the other of the front and rear wheels via the transfer device 4 and the output shaft 5 during four-wheel drive. In the transmission 2, a main transmission case 7 is connected to a clutch case 6 having a clutch 1, and a gear mechanism 8 for forward speeds of first to fourth speeds is provided in the case 7. Case 7 clutch 1
A rear case 9 is attached to the opposite side, and a gear mechanism 10 for reverse gear and EL gear is provided within this case 9. That is, the main shaft 11 and the counter shaft 12 from the clutch 1 are installed in parallel through both cases 7 and 9, and these main shaft 11 and counter shaft 12 are connected to the rear walls 6' and 7 of the cases 6, 7, and 9. It is pivotally supported by bearings 13 at ' and 9'. As a gear mechanism 8, first to fourth speed drive gears 14 are connected to a portion 11' of the main shaft 11 inside the main transmission case 7 in order from the clutch 1 side.
a, 15a, 16a, and 17a are integrally formed, and driven gears 14b, 15b, 16b, and 17b, which are always in mesh with each of these gears, are rotatably fitted to the subshaft 12. Between the speed driven gears 14b and 15b and the third speed and fourth speed driven gears 16b and 17b, synchronization mechanisms 18 and 19 are provided that selectively integrate one of them with the subshaft 12 to obtain each speed. There is. Further, as the gear mechanism 10, a reverse gear drive gear 20a with a small number of teeth is formed on the clutch 1 side of a portion 11'' in the rear case 9 of the main shaft 11. A shaft 21 is arranged so as to be prevented from rotating by a pin 22, and an idler gear 23 is rotatably attached to this shaft 21 by a needle bearing 24.
is also supported at both ends via thrust bearings 25 against the walls 7' and 9' on the case side, so that it rotates very smoothly. This gear 23 has an idler driven gear 20 with a large number of teeth.
b is formed and meshed with the drive gear 20a, and the idler driven gear 20b is further meshed with a Rebus driven gear of a synchronization mechanism, which will be described later, to obtain a reverse gear. By the way, the power taken out to the idler gear 23 by such gears 20a and 20b is also used for the EL gear stage, and in this sense, the power taken out to the idler gear 23 is
a and 20b serve as the first stage drive and driven gear for the EL gear stage, and the idler gear 23
A drive gear 26a with a small number of teeth at the second stage for the EL gear stage is formed. Next, an intermediate gear 27 that serves as a speed reducer and a rotating direction converter is fitted into a portion 11'' on the main shaft 11 side at a location that coincides with the drive gear 26a via a needle bearing 28, and both ends are connected to the main shaft 11 side receiving part 11''. 2
9. It is positioned and held rotatably by a spacer 30 between it and the bearing 13, and this intermediate gear 2
A second-stage driven gear 26b having a larger number of teeth than the gear 26a is formed at 7 and meshes with it. Further, the intermediate gear 27 has an EL gear shift gear 3 which has a smaller number of teeth than the gear 26b.
A drive gear 26c in the third stage is formed, and this gear 26c meshes with a driven gear 23d in the third stage, which is rotatably attached to the subshaft 12 via the sleeve 31. Furthermore, a synchronizing mechanism 32 is provided on the subshaft 12 on the clutch side of the gear 26d, and this synchronizing mechanism 32 has a sleeve 34 that is integral with the hub 33 that is integrally spline-coupled to the subshaft 12 in the rotational direction. The sleeve 34 is spline-fitted so as to be movable in the axial direction, and by moving the sleeve 34 toward the gear 26d, it is fitted to the subshaft 12 in synchronization. A reverse driven gear 20c for reverse gear having a larger number of teeth than the idler driven gear 20b is formed on the outer circumference of the sleeve 34, and by moving the sleeve 34 in the opposite direction, the gear 20
c meshes with gear 20b. Incidentally, the arrangement of each part of the gear mechanism 10 is actually as shown in FIG. In the transmission system from the transmission 2 configured in this manner, the final reduction device 3 is an output gear 3 integrally formed on the clutch 1 side of the subshaft 12 of the transmission 2.
A final reduction gear 36 meshes with the gear 5, and the gear 36 is connected to, for example, a rear wheel for direct driving via an actuating device 37 and an axle shaft 38. The transfer device 4 includes a transfer shaft 39 rotatably supported perpendicular to the final reduction gear 36.
The shaft 39 is provided with a transfer gear 40 that constantly meshes with the gear 36 and idles, and a clutch 41 for integrally connecting the gear 40 with the shaft 39 for switching between two- and four-wheel drive. and transfer shaft 3
9 is further configured to transmit power to the output shaft 5 via a pair of bevel gears 42 and 43, so that power is also transmitted to the front wheels during four-wheel drive. Since the present invention is constructed in this manner, the shift pattern is as shown in FIG. 4 based on the arrangement of the respective transmission gears of the gear mechanisms 8 and 10. The engine power input to the main shaft 11 of the transmission 2 by the clutch 1 causes the gears 14a and 14 of the gear mechanism 8 to
b, 15a and 15b, 16a and 16b, 17a and 17b are meshed and idle, and the synchronization mechanism 18,
By the operation 19, the power shifted from the first speed to the fourth speed is taken out to the subshaft 12. On the other hand, in the gear mechanism 10, the power input to the main shaft 11 causes the drive gear 2 for reverse gear to shift.
0a and the idler driven gear 20b, the idler gear 23 is rotated at a reduced speed by the drive gear 26a and the driven gear 26b of the idler gear 23, the intermediate gear 27 is further decelerated and rotated by the drive gear 26c and the driven gear 26d of the intermediate gear 27, and the gear 26d is further decelerated by the drive gear 26c and the driven gear 26d of the intermediate gear 27. With this three-stage reduction, the gear 26d is set to an arbitrary gear ratio that is much larger than the first speed, and is constantly rotating. In addition, although the idler gear 23 rotates in the opposite direction with respect to the main shaft 11, the rotation direction is changed to the same direction as the main shaft 11 by the intermediate gear 27, and the gear 26d rotates in the opposite direction with respect to the main shaft 11, similar to the driven side of the gear mechanism 8. do. Furthermore, idler gear 23
An intermediate gear 27 is supported on the main shaft 11 side, and is located between the gear 26d and the gear 26d, and transmits a large amount of rotational torque that increases as the gear ratio increases.
Gears 26a, 26 are connected to the front and rear gears 26b, 26c.
Because d is in mesh, very stable power transmission is achieved. Therefore, when the gear 26d is integrated with the subshaft 12 by the sleeve 34 of the synchronization mechanism 32, the EL gear stage with a large gear ratio is taken out to the subshaft 12, and at this time, the clutch 41 of the transfer device 4 switches to four-wheel drive. This allows the vehicle to fully demonstrate its performance as a four-wheel drive vehicle, such as when climbing steep hills. Further, by moving the sleeve 34 of the synchronizing mechanism 32 in the opposite direction and meshing the reverse driven gear 20c with the idler driven gear 20b, a reverse gear similar to the conventional one can be obtained.

【Effect of the invention】

As is clear from the above description, according to the present invention, the gear group of the EL gear stage, which is a two-shaft, constantly meshing type and is arranged adjacent to the gear group of the reverse gear, uses the drive and idler gears 20a, 20b of the reverse gear as they are. Intermediate gear 2 for deceleration and rotation direction conversion is used.
7 is attached to reduce the speed in three stages, the gear ratio of the EL gear stage can be set to an arbitrarily large value. Also, a part of the reverse gear group is used as the EL gear group, but there is no change in gear ratio or shift operation in reverse gear, and the same gears are driven in the EL gear group. Since it is not shared with the drive and the drive, the degree of freedom in selecting the gear ratio increases. Furthermore, since the EL gear stage is constructed on three basic axes: the main shaft, counter shaft, and reverse idler gear shaft of the transmission, the structure is not complicated and can be manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a skeleton diagram showing a transmission system when applied to a four-wheel drive vehicle as an example of the present invention, Fig. 2 is a longitudinal cross-sectional view of the main part (-cross-sectional view in Fig. 3),
FIG. 3 is a cross-sectional view taken from FIG. 2, and FIG. 4 is a diagram showing a shift pattern. 2...Transmission, 10...Gear mechanism, 11...Main shaft, 12...Subshaft, 20a...Reverse drive gear, 20b...Idler driven gear, 20c
... Reverse driven gear, 23 ... Idler gear shaft, 26a ... Drive gear, 26b ... Driven gear, 26c ... Drive gear, 26d ...
Driven gear, 27... intermediate gear, 32... synchronization mechanism.

Claims (1)

[Claims] 1. In a gear mechanism that obtains an emergent low gear that has a larger gear ratio than the reverse gear and the first gear, the idler gear of the idler gear shaft is engaged with the reverse gear drive gear of the main shaft to perform the first gear deceleration. The drive gear of the idler gear shaft is meshed with the driven gear of the intermediate gear on the main shaft, which also functions as a speed reducer and rotational direction converter, to perform a second stage of deceleration, and the drive gear of the intermediate gear is meshed with the driven gear of the countershaft to achieve a third stage. A gear group for an emergent low conversion stage is configured to perform gear deceleration, and the driven gear is integrated with the secondary shaft by the synchronization mechanism of the countershaft to obtain an emergent low gear stage, which is formed in the synchronization mechanism. A vehicle transmission characterized in that a reverse gear driven gear is configured to mesh with the idler gear to obtain a reverse gear.