JPH0513873B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an axle end joint structure, and particularly to an axle end joint structure in a drive axle with a steering device.

[Conventional technology]

In general, in a conventional arrangement, the drive axle structure with a steering device consists of a non-rotating tubular axle extending across the width of the vehicle, a spherical part formed at the end of the non-rotating tubular axle, a non-rotating hollow part located on the wheel side. Rotation is provided on the spherical surface of the spherical surface by an axle case, a pair of king pins that are attached to the end surface of the axle case and are located approximately on a diameter in the vertical direction with respect to the spherical surface, and a king pin bearing that pivotally supports each king pin. It has a movably mounted nutcle.

A constant velocity joint is arranged within the space formed by the spherical part, the axle case, and the knuckle. Moreover, the outer ring of the constant velocity joint is coupled to a drive shaft rotatably disposed within the axle case on the wheel side, and the inner ring of the constant velocity joint is rotatably supported within the tubular axle on the vehicle body side. It is connected to the axle shaft.

In this conventional drive axle structure, in order to prevent dust from entering the constant velocity joint, a dustproof annular seal is attached to the end of the nut so that it slides on the spherical surface of the spherical part. .

In this conventional arrangement, the sealing constraint is that the tip of the nut, in other words,
The dustproof seal gets in the way and makes it difficult to ideally position the seal relative to the spherical surface of the tubular axle. The spherical portion of the drive axle structure described above serves as a member that supports the load as part of the axle.

Therefore, with the shape of the rotating body centered around the axle shaft processed using conventional lathes, it is not possible to make the neck or root part thinner due to strength reasons, so it is not possible to secure the seal sliding surface necessary for steering.
The steering angle is kept within approximately 30 degrees.

In addition, as a constraint on the placement of the constant velocity joint,
The tip of the spherical part formed at the end of the tubular axle abuts or interferes with the spherical surface of the large-diameter outer ring of the constant velocity joint, thereby changing the rotation angle of the drive shaft disposed within the axle casing, and thus the spherical part. The rotation angle of the nut, that is, the steering angle, is kept within about 30 degrees.

However, in reality, the internal structure of the constant velocity joint is such that it can handle angles up to around 40 degrees, so the arrangement of the seal and constant velocity joint has a steering angle function that is commensurate with that. desired.

For the above reasons, an elliptical seal has been disclosed in which the mounting surface of the seal attached to the knuckle is inclined with respect to the spherical portion of the axle end. As such, for example, Utility Model Publication No. 59-37386 and Utility Model Publication No. 37386
There is one described in Publication No. 59-37387.

First, a front wheel support device for a front wheel drive vehicle described in Japanese Utility Model Publication No. 59-37386 will be outlined. At least one of the oil seal member and the oil seal protection member is formed such that the length in the axial direction is larger at the rear than at the front when the knuckle housing is attached. When the vehicle is steered straight ahead, the knuckle housing and the trunnion socket are pivoted so that the front part of the plane including the seal edge of at least one of the oil seal member and the oil seal protection member approaches the trunnion socket shaft part from the rear part. It is installed at a predetermined angle around the supporting kingpin.

Further, an oil seal device for a front wheel support portion of a front wheel drive vehicle described in Japanese Utility Model Publication No. 59-37387 will be outlined. Regarding the oil seal member, in its natural state, the rubber seal body has an equal width over its entire circumference and is formed as a circumferential groove with an L-shaped cross section from the mounting flange to the arm portion perpendicular to this. There is. On the other hand, the reinforcing flange member, whose cut surface on the cylindrical side of the metal cylindrical flange body is inclined with respect to the flange surface, is fitted into the circumferential groove with the circumferential groove elastically tensioned and is bonded. There is. Further, the reinforcing flange member is arranged around a king pin that pivotally supports the knuckle housing and the trunnion socket so that the front part of the plane including the annular seal edge approaches the trunnion socket from the rear part when the vehicle is steered straight ahead. It is installed at an angle.

In contrast to the above-mentioned conventional arrangement, drive axles with steering devices have conventionally been disclosed in which the arrangement is opposite to the above-mentioned conventional arrangement, that is, the arrangement of constant velocity joints is reversed. The constant velocity joint is arranged in a space formed by the spherical part of the end of the tubular axle, the axle casing, and the knuckle fixed to the axle casing; however, the inner ring of the constant velocity joint is located on the wheel side. The constant velocity joint is coupled to a drive shaft rotatably disposed within an axle casing, and the outer ring of the constant velocity joint is coupled to an axle shaft rotatably supported within a tubular axle on the vehicle body side.

An example of such an axle joint structure is the one described in Japanese Patent Application Laid-Open No. 56-24226. The driven control shaft disclosed in the above publication will be explained with reference to FIG. 6.

In FIG. 6, the driven steering shaft consists of three mutually disassembly components. These components are a shank shaft 71 connected to the differential, a constant velocity joint 72, and a control shaft 74 for driving the internal sun gear (not shown) of the boss or planetary unit.
The constant velocity joint 72 connects a spherical external joint member 75 attached to the shank shaft 71 and a control shaft 74.
It consists of an internal joint member 77 attached to. The bellows 73 seals the interior of the constant velocity joint 72. The bellows 73 is removably fixed to the external joint member 75 of the constant velocity joint 72, and the neck 76 of the bellows 73 is in tight but movable contact with the control shaft 74 in the axial direction. The bellows 73 has a residual stress in the axial direction and is formed to be able to accommodate the maximum length in the axial direction. Further, the constant velocity joint 72 including the bellows 73 is
The bellows 73 can be removed without releasing its fixation.

[Problem that the invention seeks to solve]

However, in the front wheel support device for a front wheel drive vehicle described in the above-mentioned Japanese Utility Model Publication No. 59-37386, the seal is formed into a special shape to increase the steering angle; Even if the seal is configured in a special shape, it is not necessarily sufficient in terms of seal strength, sealing, durability, etc. Moreover, it is difficult to manufacture the seal, making it impractical and having problems. Was.

Furthermore, regarding the oil seal device for the front wheel support portion of a front wheel drive vehicle described in the above-mentioned Publication of Utility Model No. 59-37387, the seal must be formed into a special shape, and the strength of the seal must be However, they are not necessarily satisfactory in terms of sealing, durability, etc., or in terms of seal production, and have some problems.

Furthermore, in the drive axle with a steering device described in the above-mentioned Japanese Patent Application Laid-Open No. 56-24226, although the control shaft 74, which is a drive shaft with a small diameter of the constant velocity joint 72, is located on the wheel side. First, in order to prevent dust from entering the constant velocity joint 72, a bellows 73, which is a dustproof seal, is installed between the spherical external joint member 75, which is the outer ring of the constant velocity joint 72, and the control shaft 74, which is the drive shaft. Since the tip of the tubular axle 78 abuts against the outer circumferential surface of the bellows 73, which has a large diameter, the bellows 73 interferes and reduces the rotation angle of the drive shaft disposed inside the axle casing. The rotation angle of the knuckle relative to the axle 78, that is, the steering angle, is subject to restrictions in the same manner as described above.

Therefore, the purpose of this invention is to solve the above problems, and when the steering angle, that is, the refraction angle of the joint part in the spherical part of the axle end is increased, and this structure is adopted in a vehicle, the vehicle To provide a joint structure of an axle end which can secure the strength of the axle while improving the turning performance.

[Means for solving problems]

In order to achieve the above object, the present invention is configured as follows. That is, the present invention provides a spherical part provided at the end of a non-rotating axle, a non-rotating axle case on the wheel side, and an axis fixed to the axle case and rotatable around a king pin attached to the spherical part. In an axle end joint structure having a supported knuckle, a seal attached to the knuckle and slidingly contacted on the spherical surface portion, and a constant velocity joint provided at the end of the axle shaft disposed within the spherical surface portion, the axle end is attached to the knuckle. The present invention relates to an axle end joint structure, characterized in that the seals are disposed in an inclined intersecting state with respect to the kingpin, straddling kingpin bearings that support the kingpin installed above and below.

Further, in this axle end joint structure, the attachment position of the seal is set at approximately the maximum diameter position of the spherical portion of the axle end.

Further, in this axle end joint structure, an end portion of the axle shaft disposed within the spherical portion of the axle end constitutes an outer ring of the constant velocity joint.

[Effect]

Since the present invention is configured as described above, it operates as follows. That is, in the joint structure of this axle end, the seal attached to the knuckle is arranged in an inclined intersecting state with respect to the king pin, straddling the king pin bearing that supports the king pin installed above and below, so that the seal The center of the sliding surface on the spherical surface can correspond to a large steering angle of the tire.

In addition, since the installation position of the dustproof seal is set at approximately the maximum diameter position of the spherical part of the axle end, it can pass over the spherical surface with only the bending allowance of the rubber during assembly, and the seal rubber and its retainer can be easily attached. There is no need to separate and assemble parts. Furthermore, when the dustproof seal scrapes off mud etc. adhering to the spherical surface, it hits the spherical surface obliquely, so there is less resistance, and there is no need to mold the seal into a special shape.
There are no problems in terms of sealing, durability, etc., or in terms of manufacturing the seal, and the seal attached to the knuckle is not obstructed by the axle end, and the knuckle is It is possible to move further on the spherical surface.

Therefore, since there is little interference between the axle shaft and the axle end during steering, it is possible to increase the turning angle of the tires, and in turn, it is possible to reduce the turning radius of the vehicle and improve the turning performance.

Embodiments Hereinafter, embodiments of the axle end joint structure according to the present invention will be described with reference to the following.

FIG. 1 shows an embodiment of an axle end joint structure according to the present invention. Regarding this joint structure, the structure of the spherical seal is such that a ring-shaped seal 3 made of rubber, felt, etc. attached to the knuckle 2 comes into contact with the spherical part 1 provided at the end of the axle end 9 to prevent foreign matter from entering. It is prevented. This seal 3 is disposed diagonally or inclined across the king pin bearing 19 that supports the upper and lower king pins 4, 4, and the seal 3 is disposed in an ideal position. . When the knuckle 2 swings around the king pin 4, the seal 3 slides in close contact with the spherical surface of the spherical portion 1, thereby performing a sealing function.

Further, the constant velocity joint 12 is connected to the tubular axle 2
It is arranged in a space formed by a spherical part 1 formed at the end of the axle 6, that is, an axle end 9, an axle case 20, and a knuckle 2 fixed to the axle case 20. And constant velocity joint 1
The inner ring of 2 is the axle case 20 on the wheel 24 side.
A drive shaft 25 rotatably disposed within
and the outer ring 1 of the constant velocity joint 12
1 is coupled to an axle shaft 5 rotatably supported within a tubular axle 26 on the vehicle body side.

Axle shaft 5 is supported by bearings 7. Further, the oil seal 8, which is tightened in the radial direction using a lip and can seal rotating or reciprocating parts, prevents differential oil from entering the joint side. The interference between the tip of the axle end 9 and the knuckle 2 limits the length beyond the king pin 4, so in order to ensure the swinging length of the seal 3, the part of the axle shaft 5 that interferes with the axle end 9 must be A structure as thin as possible is preferable.

The arrangement of the axle shaft 5 is such that the thinnest part is the interference site, so the axle shaft 5 is arranged in the opposite direction to the normal direction, that is, the outer ring 11 of the constant velocity joint 12 is provided at the end of the axle shaft 5. This is effective for the structure of the axle shaft 5. For example, if the thin part of the axle shaft 5 is set so that it can be twisted when an excessive input is applied, it can also be used to protect other more expensive equipment parts.

Furthermore, in order to effectively utilize the length of the sliding surface on the spherical portion 1 of the seal 3, it is desirable that the seal 3 be located at the center of the sliding surface when the vehicle is traveling straight. For this reason, as for the seal shape, we focused on the fact that the upper and lower parts of the seal 3 hardly move as the knuckle 2 swings, as a way to achieve an ideal arrangement while maintaining a perfect circular shape that is easy to manufacture and has reliable functionality. , it is only necessary to place only the upper and lower central portions at ideal positions. For example, as shown in FIG. 1, the seal 3 is disposed across the upper and lower king pins 4 in an intersecting state obliquely inclined with respect to the king pin 4.

Next, with reference to FIGS. 1, 2A, 2B, 3A, and 3B, an example in which the knuckle 2 is divided into two parts and the seal 3 is placed between them will be described.

As a structure for fixing the seal 3 in the above position,
As shown in FIG. 1, the knuckle 2 is divided into upper and lower halves and is composed of knuckle members 2a and 2b, and the seal 3 is sandwiched between the knuckle member 2a and the knuckle member 2b in a sandwich-like manner, thereby making the seal 3 extremely strong. can be attached to Natsukuru 2. The structure of the knuckle 2 divided into the knuckle portion 2a and the knuckle 2b is shown in more detail in FIGS. 2A, 2B, 3A, and 3B.

FIG. 2A shows a perspective view of the knuckle portion 2a, that is, the knuckle portion on the upper side, and FIG. 2B shows a sectional view thereof. FIG. 3A shows a perspective view of the knuckle portion 2b, that is, the lower knuckle portion, and FIG. 3A shows a sectional view thereof. Natsukuru part 2 on Atsupa side
The king pin hole 13 of a is the lower side knuckle part 2.
It can be co-processed with the king pin hole 14 of b.

Further, the notch step portion 15 of the knuckle portion 2a is configured to fit with the protruding step portion 18 of the knuckle portion 2b, and the protruding step portion 17 of the knuckle portion 2a is configured to fit with the notch step portion 16 of the knuckle portion 2b. has been done. The notch step portion 15 and the protruding step portion 18 have different depths, forming a gap, and the seal 3 is sandwiched and fixed in the gap. By installing the seal 3 on the knuckle 2 in this manner, the seal 3 is installed diagonally across or intersecting the kingpin bearing 19 around the kingpin 4. As a result, one of the upper and lower kingpins 4 becomes outside the seal 3 and becomes exposed, so a kingpin seal 6 is provided around the kingpin bearing 19 to cope with this.

Another example of tilting the seal 3 attached to the knuckle 2 will be described with reference to FIGS. 4A, 4B, and 4C. In the drawing, the knuckle 2 is not divided into two parts, but the technical concept of inclining at a predetermined angle, which will be described later, can of course be applied to the above-mentioned knuckle 2 divided into two parts.

4A, 4B, and 4C show an example of the knuckle 2 attached to the axle case 20 in the axle end joint structure according to the present invention. Figure 4A is a plan view of the nut case 2, and the axle case 2
The mounting surface 21 of the knuckle 2 mounted on the shaft is inclined at a predetermined angle θ, for example, about 4°, with respect to the axis of the axle, that is, the axis of the axle case 20.
FIG. 4B is a sectional view taken along line HH in FIG. 4A. By inclining the mounting surface 21 of the knuckle 2 by a predetermined angle θ, for example about 4°, with respect to the axis of the axle case 20, the mounting surface 21 of the knuckle 2 is offset by a distance l, for example about 2 mm. Fourth
Figure C is a front view seen from the direction of arrow G in Figure 4A. It is clearly shown that the mounting surface 21 of the knuckle 2 is inclined by a predetermined angle θ.

Next, regarding the case where the seal 3 is arranged diagonally across the upper and lower king pins 4, referring to Figures 5A and 5B, the case where the seal 3 is inclined with respect to the spherical part 1 will be explained. The mounting structure will be discussed.

In FIGS. 5A and 5B, a spherical portion 1 is integrally provided at the end of the axle end 9. As shown in FIG. In FIG. 5A, the seal 3 is fixed to the knuckle 2, and the seal 3 is shown in positions A, B, and C.
In FIG. 5B, the seal 3 is shown in positions D, E, and F.

In the case shown in FIG. 5A, the mounting angle of the seal 3, that is, the predetermined angle θ, is, for example, 4°. At position A of seal 3, the steering angle is
It corresponds to 0°. The B position of the seal 3 corresponds to the maximum shear angle of the inner ring, that is, the steer angle is 38 degrees, and the C position of the seal 3 corresponds to the maximum shear angle of the outer ring, that is, the steer angle of the outer ring is 30 degrees. By setting the seal mounting angle at an angle of 4 degrees when installing the seal 3 in this way, the sliding length of the seal 3 on the cutting angle side of the inner ring can be increased and the entire spherical surface of the spherical portion 1 can be effectively used. I can do it.

What is shown in FIG. 5B is a case where the mounting angle of the seal 3, that is, the predetermined angle θ, is, for example, 0°. The D position of the seal 3 corresponds to a steer angle of 0°. The E position of the seal 3 corresponds to the maximum shear angle of the inner ring, that is, the steer angle of the inner ring is 34 degrees, and the F position of the seal 3 corresponds to the maximum shear angle of the outer ring, that is, the steer angle of the outer ring is 27 degrees. In this way, when installing the seal 3, if the seal installation angle is set to 0 degrees, the range on the spherical surface of the spherical part 1 from end to end, in other words, the range until the seal 3 contacts the axle end 9. It cannot be used completely, and the length indicated by the symbol L ends up being wasted even though there is plenty of room.

One embodiment of the axle end joint structure according to the present invention is constructed as described above, but it goes without saying that the present invention is not limited to the detailed structure described above.

For example, instead of dividing the knuckle into two and fixing a seal between them, it is also possible to install a seal in the knuckle itself, for example, by forming a groove on the inner peripheral surface and installing the seal within the groove. Of course it can be done.

Also, even if the structure is conventional, if the axle shaft is placed in the opposite direction, and the seal mounting surface is tilted toward the inside of the vehicle and the rear toward the outside, the difference in the turning angle between the inner and outer wheels of the Atsukerman steering tire can be minimized. By distributing the length of the seal sliding surface, the turning angle can be increased and the turning radius of the vehicle can be reduced.

Furthermore, regarding how to tilt the seal mounting surface,
Slanting the machined surface of the nut has the advantage that it is not necessary to create a special shaped seal. It has the potential to achieve 40° and 40° by distributing the seal to the left and right side against the kingpin, so when making a difference in the tire angle of the inner and outer wheels for Atsukerman steering, the difference is 1/ For example, if you take measures such as tilting the tip of the axle end by 1/2 of the angle difference in the front and rear direction to prevent interference, you can easily adjust the angle of the rudder to a large angle of 45° or 35°. You can get the angle. Of course,
The internal constant velocity joint also requires the ability to handle this. Such ability is generally a function possessed by constant velocity joints.

〔Effect of the invention〕

Since the present invention is configured as described above, it has the following effects. In other words, the joint structure of the axle end is such that the seal, which is attached to the nut and slides on the spherical surface of the axle end to prevent dust, straddles the king pin bearings that support the king pins installed above and below, and connects the king pin to the king pin. Since the seals are arranged in an inclined intersecting state, the part of the seal related to the steering angle can be set at the center on the sliding surface of the spherical part to cope with a large tire turning angle.

In addition, since this seal 3 is installed at approximately the maximum diameter position of the spherical surface of the axle end, it can pass over the spherical surface only by bending the seal rubber during assembly, and the seal 3 and There is no longer a need to separate and assemble parts of the retainer.

Furthermore, when the dustproof seal scrapes off mud etc. adhering to the spherical part, it hits the spherical part obliquely, so there is less resistance. Furthermore, the turning radius of the vehicle can be reduced, and the dustproof seal at the axle end can be easily assembled. Furthermore, the watertightness of the seal is greatly improved, and a small portion of the axle shaft outer can be used as a torque fuse to prevent damage to other large devices and parts.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the joint structure of the axle end of a drive axle with a steering device according to the present invention, FIG. Fig. 2A is a sectional view, Fig. 3A is a perspective view showing the lower side knuckle part of the knuckle,
Figure B is a sectional view of Figure 3A, Figure 4A, Figure 4B and Figure 4C are examples of a nutcle attached to the axle case, Figure 4A is a plan view of the nutcle, Figure 4B is a sectional view taken along line H-H in Figure 4A, Figure 4C is a front view seen from the direction of arrow G in Figure 4A, and Figure 5A is a view of the case where the knuckle is tilted. An explanatory diagram showing the relationship between the spherical part of the axle end and the seal of the nut;
FIG. 5B is an explanatory view showing the relationship between the spherical part of the axle end and the seal of the knuckle in a conventional joint structure, and FIG. 6 is a sectional view showing the conventional joint structure of the axle end. 1... Spherical part, 2... Knuckle, 2a... Knuckle part on the top side, 2b... Knuckle part on the lower side, 3... Seal, 4... King pin, 5...
Axle shaft, 6...King pin seal, 7
... Bearing, 8 ... Oil seal, 9 ... Axle end, 11 ... Outer ring, 12 ... Constant velocity joint, 19 ... King pin bearing, 20 ...
...Axle case, 21...Natsukuru mounting surface,
A, B, C, D, E and F...Seal installation angle relative to steer angle.

Claims (1)

[Claims] 1. A spherical part provided at the end of a non-rotating axle, a non-rotating axle case on the wheel side, and rotatable around a kingpin fixed to the axle case and attached to the spherical part. In the axle end joint structure, the axle end has a pivotally supported knuckle, a seal attached to the knuckle and in sliding contact on the spherical surface, and a constant velocity joint provided at the end of the axle shaft disposed within the spherical surface. An axle end joint structure, characterized in that the attached seal is disposed in an inclined intersecting state with respect to the king pin, spanning king pin bearings that support the king pin installed above and below. 2. The axle end joint structure according to claim 1, wherein the attachment position of the seal is set at approximately the maximum diameter position of the spherical portion of the axle end. 3. The axle end joint structure according to claim 1, wherein an end portion of an axle shaft disposed within the spherical portion of the axle end constitutes an outer ring of the constant velocity joint.