JPH0810023B2 - Bearing device of automatic transmission for vehicle - Google Patents

Description

Detailed Description of the Invention

[Industrial applications]

The present invention relates to a bearing device for an automatic transmission for a vehicle.

[Prior art]

In the structure of a double row conical roller bearing or an angular contact ball bearing, a bearing structure in which oil seals are provided on both outer sides is known. This is used when grease is sealed in the bearing and prevents the grease from leaking to the outside. However, in an automatic transmission for a vehicle, the lubricating oil for the hypoid gear or spiral gear on the torque converter case side and the lubricating oil used for the automatic transmission gear mechanism on the transmission case side are of different types for their purposes. Is used. The hypoid gear uses hypoid gear oil that uses an extreme pressure additive, while the automatic transmission gear mechanism is the working fluid of the torque converter and requires the timing adjustment of the engagement and disengagement of each friction element. , Working fluids for satisfying friction characteristics, for example commercially available
DEXRON etc. are used. Usually, in order to separate and seal such two different kinds of oil, a double lip oil seal or the like is provided outside one side of the bearing. In this case, the effect of suppressing the mixing of both oils is not improved compared to the single oil seal, but due to the structural reason that the bearing and the oil seal are arranged in series, the oil seal is fitted and held. It is necessary to provide structural consideration such as providing a holder for the shaft and a sleeve for the oil seal on the shaft. As a prior art in which an oil seal is press-fitted between two taper roller bearings, there is Japanese Utility Model Publication No. 55-117324.

[Problems to be Solved by the Invention]

However, in the automatic transmission, the axial distance between the constituent members of the automatic transmission gear mechanism, for example, the outer peripheral portion of the reverse clutch drum and the drive pinion shaft is set to be small (the central axis of the crankshaft and the drive pinion shaft are Closer distance from the center axis is a serious requirement for the layout of the on-board engine),
When the drive pinion shaft is pivotally supported by the bearing provided on the bearing plate, the holder, the sleeve, the lock nut of the sleeve, and the like interfere. Therefore, as shown in FIG. 3, in order to avoid interference with the above nuts, the oil seal 31, the holder 30, the sleeve 32, and the lock nut 34 for holding the sleeve 32, etc. of the taper roller bearing 10 are provided in the automatic transmission gear mechanism. The axial extension presents another problem of increasing the overall axial length of the automatic transmission. Further, in the case of the above-mentioned prior art, since there is only one oil seal, the oil flows from one chamber to the other chamber due to the pressure difference between the two chambers separated by the oil seal, the pumping action of the main lip of the oil seal, and the like. There is a problem. The present invention has been made based on the above circumstances, and by installing two oil seals between the double-row bearings and providing a pleaser passage, the protrusion of the holder and the like to the outside of the bearing is avoided and the layout is improved. An object of the present invention is to provide a bearing device for an automatic transmission for a vehicle, which prevents the different lubricating oils in the two chambers from flowing into the other chamber without affecting the above. It is a thing.

[Means for solving problems]

As a means for achieving this object, the present invention is a drive pinion in which power is transferred from an automatic transmission in the transmission case to a differential gear device in the torque converter case through a bearing plate that separates the inside of the torque converter case from the inside of the transmission case. In a bearing device that rotatably supports the shaft on the bearing plate,
The bearing device is a double-row bearing that is located at an intermediate portion in the axial direction and has a pair of oil seals arranged oppositely between the outer race and the inner race. The outer race has a space between the pair of oil seals. And a breather hole communicating with the breather passage provided in the bearing plate.

[Action]

In the present invention employing such means, the oil in the torque converter case and the oil in the transmission case are separated by the pair of oil seals incorporated in the double-row bearing, so that the pair of oil seals are prevented from leaking. Even if there is, the leaked oil is discharged from the gap between the pair of oil seals to the breather passage provided in the bearing plate through the breather hole provided in the outer race of the double row bearing.

【Example】

Hereinafter, one embodiment of the present invention will be specifically described with reference to FIGS. 1 and 2. FIG. In these drawings, reference numeral 1 is a torque converter case connected to the engine body, and the torque converter case 1 is connected to a transmission case 3a via a bearing plate 2. The torque converter 4 arranged in the torque converter case 1 has its input shaft 4a extended to the transmission case 3a side through the bearing plate 2.
The automatic transmission gear mechanism 5 is linked to it. As is well known, the automatic transmission gear mechanism 5 includes a reverse clutch.
5a, forward clutch 5b, low reverse brake 5c, one-way clutch 5d, reverse sun gear 5e, forward sun gear 5f, ring gear 5g, brake band 5h, etc., and these friction engagement devices are engaged or disengaged. The extension case 3b arranged behind the transmission case 3a is shifted.
Power is transmitted to the reduction driven gear 7 of the final gear unit via the reduction drive gear 6 and power is transmitted to the rear drive shaft 9 via the transfer clutch 8. The bearing plate 2 has a double row of tapered roller bearings 10
Is fitted in the bearing hole 11 of the bearing plate 2 and fixed to the bearing plate 2 by the outer race 10c of the double row tapered roller bearing 10, and one end of the drive pinion shaft 12 is pivotally supported. The above-mentioned reduction driven gear 7 is fixed to the other end of the drive pinion shaft 12 via a lock washer 7b with a lock nut 7a,
The reduction driven gear 7 has a cylindrical boss portion 7c at both ends.
The drive pinion shaft 12 is formed by the bearing 19 pressed into the rear end of the transmission case 3a and the bearing 20 pressed into the front of the extension case 3b.
A drive pinion 13 is provided at the shaft end that extends from the transmission case 3a side to the torque converter case 1 side through the bearing plate 2. The rollers 10a and 10 of the taper roller bearing 10 are
b is separated, and there are two oil seals 1 in this gap.
4, 14 'are installed with the main lips 15, 15' inside, respectively, and the springs 21, 22 provide a sealing property between the main lips 15 and the outer peripheral portions of the inner races 23, 24 of the double row tapered roller bearing 10. It is provided to improve. Furthermore, the inner races 23 and 24 have lock nuts 26 and lock washers 25.
Is pivotally supported by. Also, taper roller bearing
The outer race 10c of 10 has a breather hole 16,
The breather hole 16 passes through a breather passage 17 formed in the bearing plate 2 and communicates with the atmosphere. In the figure, reference numeral 18 is a differential gear unit provided on the torque converter case 1 side, and the crown gear 18a of the differential gear unit 18 is
It is meshed with the drive pinion 13. In such a configuration, each of the above-mentioned oil seals 14, 14 '
The torque converter case 1 side and the transmission case 3a side through the drive seal the drive pinion shaft 12 with lubricating oil. And
Even if an oil leak occurs, the leaked oil will flow into the breather passage 17 through the breather hole 16 and will not enter the other area beyond the oil seal on the opposite side. The structure of the oil seal is not limited to the bearing portion of the drive pinion shaft 12, but it goes without saying that the oil seal can be used for the shaft portion that is supported over the regions where different lubricating oils are used.

【The invention's effect】

As described above, according to the present invention, the oil in the torque converter case and the oil in the transmission case are separated by the pair of oil seals incorporated in the double-row bearing, and there is no leakage in the pair of oil seals. However, since the leaked oil is discharged from the gap between the pair of oil seals to the breather passage provided in the bearing plate through the breather hole provided in the outer race of the double row bearing, the oil in the torque converter case and the transmission case It is possible to reliably prevent mixing with the oil inside. Here, since the pair of oil seals are located in the axial middle portion of the double-row bearing and are installed between the outer race and the inner race, the bearing retainer, the holder, the sleeve, and the sleeve for mounting the oil seals. Since no members such as lock nuts are needed at all, the number of parts and the number of assembly steps can be significantly reduced, and the axial length of the bearing device can be greatly reduced, shortening the automatic transmission.
It can contribute to weight reduction and rigidity improvement.

[Brief description of drawings]

FIG. 1 is an overall vertical sectional side view showing an embodiment of the present invention, FIG. 2 is an enlarged vertical sectional view showing an essential part, and FIG. 3 is a longitudinal sectional view showing a conventional essential part. 1 ... Torque converter case, 2 ... Bearing plate, 3a ...
Transmission case, 3b ... Extension case, 4 ... Torque converter, 4a ... Input shaft, 5 ... Automatic transmission gear mechanism, 5a ... Reverse clutch, 5b ... Forward clutch, 5c ... Low reverse brake, 5d ... … One way clutch, 5e …… Reverse sun gear, 5f …… Forward sun gear, 5g …… Ring gear, 6 …… Reduction drive gear, 7 …… Reduction driven gear, 8 …… Transfer clutch, 9…
… Rear drive shaft, 10 …… Taper roller bearing, 11 …… Bearing hole, 12 …… Drive pinion shaft,
13 …… Drive pinion, 14,14 ′ …… Oil seal, 1
5,15 '…… Lip, 16 …… Breather hole, 17 …… Breather passage, 18 …… Differential gear unit, 18a…
… Crown gear.

Claims (1)

[Claims] 1. A drive pinion shaft for transmitting power from an automatic transmission in a transmission case to a differential gear device in a torque converter case through a bearing plate for partitioning a torque converter case and a transmission case into the bearing plate. In the bearing device for rotatably supporting, the bearing device is a double-row bearing in which a pair of oil seals are arranged so as to face each other between the outer race and the inner race at an axially intermediate portion, and the outer race is used. A bearing device for an automatic transmission for a vehicle, characterized in that a breather hole is provided to connect a gap between the pair of oil seals to a breather passage provided in the bearing plate.