JPS5845362B2 - Hanfudoushikikudoushiyajik - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semi-floating drive axle in which the wheels are mounted directly on the drive shaft and are supported in the axle tube via wheel bearings.

Generally, the driving torque from the engine is transmitted to the wheel hub 3 and the wheels 4 via the spline section 2 of the drive shaft 1 and the spline 2' provided on the inner peripheral surface of the wheel hub 3, as shown in Fig. 1. As shown in Fig. 2, there is a method of integrally forging the drive shaft 5 and the wheel hub 5a to transmit the power.
In any case, the following problems exist.

In the case of the embodiment shown in FIG. 1, after the bearing 6 is press-fitted into the drive shaft 1, it is press-fitted into the axle tube 7, the seal 8 and the bearing retainer 9 are tightened, and the bearing 6 is attached to the vehicle body 10.

Thereafter, the spline 2' of the wheel hub 3 to which the brake 11 and the wheel 4 are attached are engaged and matched with the spline portion 2 of the drive shaft 1, and the nut 12 or the like is used to secure the spline 2'.

On the other hand, in the case of the embodiment shown in FIG.
After the bearing 5b is press-fitted, the bearing 5b is tightened and fixed with a nut 5c.

Then, the brake 16 and the axle 17 are attached to the wheel hub 5a.
Attach the bolt 15 of the bearing holder 14 to the wheel hub 5.
When the bearing unit mounted on the drive shaft 5 is screwed into the axle pipe 18 and tightened by aligning it with the tightening hole 19 of a.
attached to.

However, in either case, there is a press-fitting process for assembling the bearing, and a dedicated assembly machine such as a press is required (otherwise, the life of the bearing will be significantly shortened due to creep, etc.).

Furthermore, since there are a large number of parts, assembly and disassembly work becomes complicated, and processing work for the parts increases, leading to increased costs and decreased reliability.

Furthermore, the embodiment shown in FIG. 1 has a problem in terms of strength because the load and drive torque from the wheels 4 must all be borne by the spline portions 2.

Further, in the embodiment shown in FIG. 2, the wheel hub 5a is connected to the drive shaft 5.
An increase in manufacturing costs is unavoidable because the parts are integrally forged.

In view of the above-mentioned drawbacks of the conventional semi-floating drive axle, the present invention has been developed to improve and eliminate these drawbacks, and the structure of the present invention will be described below with reference to embodiments shown in the drawings.

In Fig. 3, reference numeral 21 denotes a bearing inner ring having a single row of transfer grooves on its outer diameter, with a wheel hub 22 at one end and a drive shaft 23 at the other end by friction welding or electron beam welding. The rolling elements 24, the bearing outer ring 25, and the seal 26 are assembled and integrated to form a bearing unit 27.

In addition, when the bearing unit 27 is integrated using the friction welding method, the bars 1J28, 28' are attached at the joint.
occurs.

The burr 28 at the joint with the wheel hub 22 does not pose a problem in the structure of the bearing unit 27, but the burr 28' at the joint with the drive shaft 23 causes an obstacle when assembling the rolling element 24 and the seal 26, so the outer diameter The paris in the section needs to be scraped off.

The brake 29 and the wheel 30 are attached to the wheel hub 22 of the bearing unit 27 configured as described above, and the bearing unit 27 is inserted into the axle tube 32 integrated with the vehicle body 31 with the seal 33 interposed. Assembly work is complete.

At this time, the outer diameter of the bearing outer ring 25 and the inner diameter of the axle tube 32 are configured to form a clearance fit, and the bearing unit 27 can be inserted into and removed from the axle tube 32 without using a press or the like.

The drive torque from the engine in the semi-floating drive axle constructed as described above is transferred to the wheels 30 through the drive shaft 23, bearing inner ring 21, and wheel hub 22, which are integrated by friction welding or electron beam welding. communicated.

On the other hand, part of the load from the wheel 30 is supported by the axle tube 32 via the wheel hub 22, the rolling elements 24 of the bearing inner ring 21, and further the bearing outer ring 25, and the remaining part is supported by the bearing unit 27.
The drive shaft 23 is supported by bearings inside the vehicle body through each of the drive shafts 23 and 23, respectively.

This allows drive torque to be transmitted to the wheels 30 without the need for splines, and also provides a strong semi-floating drive axle since the load from the wheels 30 is divided.

As explained above, the present invention provides a semi-floating drive axle in which the wheels are directly attached to the drive shaft and supported by the axle tube through the wheel bearings. Since the wheel hub for mounting the wheel is joined to the end by friction welding or electron beam welding, it is possible to provide a bearing that integrates the wheel hub, bearing inner ring, and drive shaft as a single unit. Compared to a wheel hub and drive shaft that are integrally forged, processing work is greatly simplified by reducing assembly man-hours, assembly difficulty, and the number of parts, leading to lower manufacturing costs and improved reliability. .

Furthermore, since the wheel bearing and the axle are integrated, assembly and disassembly work is facilitated.

Furthermore, since the bearing is constructed as a single unit, drive torque and load are reliably transmitted, and since the spline portion is omitted, excellent strength is achieved.

[Brief explanation of the drawing]

1 and 2 are longitudinal sectional side views of a conventional semi-floating drive axle, and FIG. 3 is a longitudinal sectional side view of a semi-floating drive axle according to the present invention. 1.5.23... Drive shaft, 2.2'...
・Spline, 3, 5a, 22... Wheel hub, 4, 17° 30... Axle, 7, 18, 32
...Axle pipe, 21 ...Bearing inner ring.

Claims (1)

[Claims] 1. In a semi-floating drive axle in which the wheels are directly attached to the drive shaft and supported in the axle tube via wheel bearings,
A semi-floating drive axle characterized in that a drive shaft is attached to one end of an inner ring of a wheel bearing, and a wheel hub for attaching a wheel is attached to the other end by friction welding or electron beam welding.