JPH02246832A - Propeller shaft of vehicle - Google Patents

Abstract

PURPOSE:To largely reduce the generation of centrifugal force resulting from unbalance by remarkably decreasing binding force in the direction of translation of a propeller shaft and supporting the propeller shaft by a vehicle side through an elastic body. CONSTITUTION:A propeller shaft 10 is connected to the main shaft 46 of a transmission 44 and the drive pinion shaft 52 of a final reduction gear 50 through a front joint member 14 and a rear joint member 16 provided at both ends. The front end of a vehicle is rotatably and elastically supported through a bearing 60 and a first elastic body 62 and the rear end of a vehicle is similarly supported through a bearing 68 and a second elastic body 70. When a propeller shaft main body 12 is rotated at a high speed, the propeller shaft main body 12 is translationally moved in a direction where the balance of its rotation is accomplished together with the deformation of the first and the second elastic bodies 62, 79 and the inclination of the front and rear joint members 14, 16. Accordingly, stable rotational movement can be achieved by employing automatic alignment action.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a propeller shaft that connects a power plant and a final reduction gear mounted on a vehicle.

Conventional technology This type of propeller shaft is described in the New Automotive Engineering Handbook (published by the Society of Automotive Engineers of Japan in June 1986), No. 5.
There are various kinds of propeller shafts, as disclosed in Chapter 1, Chapter 4 (pages 25 to 29), among which, for example, a two-joint type propeller shaft l is a hollow tubular type as shown in Fig. 5. It is generally composed of a propeller shaft body 2 and joint members 3.4 provided at both ends of the propeller shaft body 2.

The propeller shaft 1 has one joint member 3 connected to the output shaft of a power plant (not shown) consisting of a combination of an engine, a transmission, etc., and the other 29476 member 4 connected to the It is connected to the input shaft of an external final reduction gear, and transmits the torque generated by the power plant to the driving wheels via the final reduction gear.

By the way, when the above propeller shaft l is running at high speed,
The propeller shaft 1 is required to have high rotational balance because it is rotated at the same speed as the engine, or even faster in the overdrive stage.

For this reason, the unbalance amount of the propeller shaft 1 is measured using a dynamic balance tester, and the unbalance mass (
Attach balance weight 5 to the light part), etc.
The rotation direction is balanced.

Therefore, manufacturing and assembling the propeller shaft 1 requires a great deal of man-hours to manage its balance, and the same care must be taken during maintenance.

Problems to be Solved by the Invention However, there are problems with such conventional propeller shafts.
C is a joint member such as a cardan joint, which has a small restraining force against angular displacement but has no degrees of freedom in the =lu direction and the axial direction.A universal joint is usually used for the joint member. Therefore, propeller shaft 1
The rotational axis center of is determined as the axis passing through the joint members at both ends (front and rear).

Therefore, even if advanced balance management is performed on the propeller shaft 1, if a slight amount of unbalance remains, the centrifugal force on the unbalanced mass acts as an excitation force, which is one of the causes of vibration and noise. It had become.

Therefore, in order to reduce the above excitation force, the first measure is to reduce the unbalance ffl of the propeller shaft l as much as possible by 1u, and in this way, if we are to further improve the accuracy of balance management, There was a problem in that the work efficiency during manufacturing and assembly was significantly deteriorated, and as a result, the cost of the product was forced to increase significantly.

In view of such conventional problems, the present invention improves the self-aligning action of the propeller shaft body by devising a support structure for the propeller shaft body and significantly reducing the restraining force in the translational direction of the propeller shaft body. Take advantage of
An object of the present invention is to provide a propeller shaft for a vehicle that can significantly reduce the generation of centrifugal force caused by unbalance.

Means for Solving the Problems [In order to achieve the first object, the present invention provides a propeller shaft main body, an output shaft of a power plant, and an input shaft of a final reduction gear, each of which can be displaced in a translational direction, and The propeller shaft is connected via a joint member having a transmission function, and at least one portion of the propeller shaft body is supported on the °C vehicle body side via an elastic body.

Further, the joint member includes a pair of first joint members disposed opposite to each other. a second connecting member; and the first connecting member. an intermediate member disposed between the second connecting member, the first and second connecting members and the intermediate member are respectively locked in the rotational direction, and are tilted through a low friction member. It is desirable that they be configured so that they can be connected together.

In the propeller shaft of the present invention, the propeller shaft body and the power plant and the final reduction gear are connected via a joint member having a torque transmission function. Since torque is transmitted, no torque is applied to the elastic body that supports the propeller shaft body, and therefore, the elastic body is set to the minimum spring constant sufficient to support the propeller shaft body. (be able to.

For this reason, the propeller shaft body is connected to the power plant and the final reduction gear via a joint member that is movable in the translational direction, and the spring constant of the elastic body that supports the propeller shaft body is set to be extremely small. As a result, the propeller shaft main body can be easily moved in the translational direction, and when rotating at high speed, a self-aligning effect acts on the propeller shaft main body, so that the propeller shaft main body is moved in a direction that achieves rotational balance. It moves automatically and rotates stably, greatly reducing vibration generation.

Further, in claim 2, the bipedal joint member includes a first joint member.
Since the second connecting member and the intermediate member are each locked in the rotational direction, the first connecting member and the intermediate member are connected to each other through the intermediate member. Torque transmission is possible between the second connecting member, and by extension, between the propeller shaft main body and the power plant and the final reduction gear, and between the first and second connecting members and the intermediate member, there is a low friction member. Since the propeller shafts are connected to each other so as to be tiltable, it is possible to significantly reduce the frictional force, that is, the restraining force, during translational movement of the propeller shaft body by the low friction member.

Therefore, by configuring the diagonal member in this manner, it has sufficient durability against the transmission of large torque, and the restraint force on displacement in the translational direction can be made extremely small.

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

That is, FIG. 1 shows an embodiment of a propeller shaft 10 for a vehicle according to the present invention, and the propeller shaft 10 includes a propeller shaft body 12, a front joint member 14 and a rear joint member attached to both ends of the propeller shaft body 12. 1G.

The propeller shaft IO is composed of a hollow tubular body such as a drawn steel tube or an electric resistance welded steel tube, and a male spline 18 is formed at the vehicle front end (left side in the figure), and a male spline 18 is formed at the vehicle rear end (left side in the figure).
A flange 19 is formed at the end (right side in the figure).

Further, as shown in detail in the enlarged view of FIG. 2, the front and rear joint members 14 and 16 each have a first outer race 20 and a first outer race 20 and a first connecting member connected to the propeller shaft body 12, respectively. A second actor race 22.22a serving as a second connection member is arranged to face the first outer races 20, 20a in the axial direction. Inner laces 24 and 24a as intermediate members are arranged between them.

Receiving portions 26 into which the respective ends of the inner laces 24, 24a are inserted are formed in opposing portions of the first outer lace 20.20a and the 27th outer lace 22.22a, and the inner laces 24, 24a are inserted into the receiving portions 26. The ends of the inner races 24, 24a are each formed into a spherical shape.

A plurality of axially extending grooves 28 and 30 are formed between the outer periphery of the spherical end of the inner race 24.24a and the inner periphery of the receiving portion 26, respectively. and 30, a ball 32 as a low friction member is fitted approximately closely so as to be removable.

The ball 32 is prevented from coming off by a ball cage 34.

Furthermore, as shown in FIG. 2, the groove portion 30 formed in the mating receptacle portion 26 is a ring member formed separately from the first outer race 20° 20a and the second outer races 22, 22a. 36, and the ring member 36 is fixed to the first outer race 20° 20a and the second outer races 22, 228 by press-fit caps. The groove portion 30 is directly connected to the first outer race 20, 20a without
It can also be formed on the second outer laces 22, 22a.

By the way, the ml outer race 20 of the front joint member 14 has a female spline 3 that is fitted into the male spline 18 formed on the propeller shaft body 2.
8 are formed, and the first outer race 20 and the propeller shaft body 12 are spline-coupled via these male and female splines 18 and 38.

On the other hand, the first outer race 2 of the rear joint member I6
A flange 40 is formed on Oa, and by fixing the flange 40 and the flange 19 of the propeller shaft body 12 with bolts 42, the first outer race 22a and the propeller shaft body 12 are coupled.

Further, the second outer race 22 of the front joint member 14 is coupled to the main shaft 46 of the transmission 44 constituting the power plant via a spline 48, and the second outer race 22a of the rear restraint member 16 is It is coupled to the drive pinion shaft 52 of the final reduction gear 50 via a flange 54 .

At the top, the front joint member 14 is housed in a front joint case 58 that is fixed to an extension 56 protruding from the transmission 44, while the first outer race 20 of the front joint member 14 is supported on the inner periphery of the front joint case 58 via a bearing 60 and an annular first elastic body 62 fitted to the outer periphery of the bearing 60.

On the other hand, the rear joint member 16 is connected to the final reduction gear 50.
The first outer race 22 of the rear joint member 16 is housed in a rear joint case 6 which is fixed to the differential carrier 66 of the rear joint member 16. It is supported on the inner periphery of the rear joint case 68 via the body 70.

Accordingly, the propeller shaft main body 12 splined and flanged to the first outer races 20 and 22 has a forward end portion of the propeller shaft connected to the two-legged bearing 60.
and transmitucillin 44 via the first elastic body 62
At the same time, the rear end of the vehicle is supported on the final reduction gear 50 side via the bearing 68 and the second elastic body 70.

By the way, both ends of the propeller shaft body 12 are as follows:
It is supported on the transmission side 44 side and the final reduction gear unit 50 side via the first elastic body 62 and the second elastic body 70, but the transmission unit 44 and the final reduction gear unit 50 are supported via a mount (not shown). Therefore, in this embodiment, the transmission/14 and the final reduction gear 50 are supported on the vehicle body side. Second elastic body 62
．． 70 is on the vehicle body side.

Of course, the propeller shaft main body 12 has two legs, the first one. It is also possible to directly support the vehicle body component via the second elastic body 62, 70.

The second outer race 20a of the front joint member 14 is rotatably supported on the inner periphery of the extension 56 via a bearing 64, and the second outer race 22a of the rear joint member 16 is rotatably supported by the inner circumference of the extension 56 via a bearing 64. It is supported by being flange-coupled to the pinion shaft 50.

With the above configuration, the propeller shaft 10 of this embodiment is
The propeller shaft body 12 is connected to the main shaft 46 of the transmission 44 (power plant) and the drive pinion shaft 50 of the final reduction gear 50 via the front joint member 14 and rear restraint member 16 provided at both ends. The front end of the vehicle is connected via the bearing 60 and the first elastic body 62,
In addition, the rear end of the vehicle is rotatably and elastically supported via the bearing 68 and the second elastic body 70, respectively.

By the way, the above-mentioned front and rear restraint members 14.1
6 is between the first °r outer race 20.20a and the inner race 24.24a, and the second outer race 2
2, 22a and the inner race 24.24a are locked in the rotational direction via balls 32 fitted in the grooves 28.30, so that the torque generated by the power plant is transferred to the propeller. It becomes possible to transmit the signal to the final reduction gear 50 via the shaft 10, and the left and right drive wheels are driven by the final reduction gear 50.

Furthermore, the distance between the first outer race 20.20a and the inner race 24.24a, and between the second degree r outer race 22.22a and the inner race 24.24a is established by transferring the ball 32, respectively. Inclination (movement in the direction perpendicular to the axis) is possible, and as the ball 32 is transferred, it is also relatively moved in the axial direction. By doing so, the frictional resistance during tilting and relative movement can be significantly reduced.

Accordingly, 1-Front, rear control member 14.1
6 is the inner race 24, 24 as shown in FIG.
By being inclined at both ends of a, the propeller shaft body 12 can be displaced in the translational direction.

Here, in order for the propeller shaft main body 12 to be displaced in the translational direction, the propeller shaft main body 12 must be moved both in the direction perpendicular to the axis and in the axial direction, and the displacement in the translational direction will be an arc. In the example, it is assumed that the translation direction includes both elements in the axis-perpendicular direction and in the axial direction.

By the way, when the bipedal propeller shaft main body 12 is displaced in the translational direction, the first elastic body 62 and the second elastic body 70 supporting both ends of the propeller shaft main body 12 are deformed at °C. The first degree second elastic body 62.70
Since no torque acts on the spring constant, the spring constant can be set extremely small, and in this embodiment, it is set to the minimum value sufficient to support the propeller shaft body 12.

Therefore, when the propeller shaft main body 12 is translated, the friction force due to the balls 32 is extremely small (and the spring constants of the first and second elastic bodies 62 and 70 are set small). Coupled with this, the restraining force during the translational movement is significantly reduced.

Therefore, when the driving force is transmitted from the power plant side to the final reduction gear 50 side, when the propeller shaft body 12 is rotated at high speed, such as when driving at high speed, the propeller shaft body 12 automatically rotates. When the alignment effect is achieved, the above-mentioned 1. With the deformation of the second elastic body 62, 70 and the inclination of the front and rear joint members 14, 16, the propeller shaft body 12 is translated in a direction in which its own rotational direction is balanced.

Therefore, by utilizing the self-aligning action of the propeller shaft main body 12 in this manner, the propeller shaft 10 of this embodiment can obtain a portion where the vibration is reduced as shown in the broken line portion in FIG. 3.

That is, in FIG. 3, the vertical axis represents the vertical vibration acceleration level a of the propeller shaft and foot, and the horizontal axis represents the rotational speed N of the propeller shaft (in this example, the first-order frequency component of rotation). This figure shows a comparison of the characteristics of a conventional propeller shaft (characteristic B shown by a broken line) and that of this embodiment (characteristic A shown by a solid line).

It should be noted that essentially the same result can be obtained even if the horizontal axis represents the frequency in degrees Celsius.

In other words, in the case of a conventional propeller shaft, as mentioned above, both ends were supported via a universal joint that was free in angular displacement, translated, and rigid in the axial direction.In other words, the elasticity of the pin support at both ends It has axial characteristics.

Therefore, conventionally, rigid body vibration of the propeller shaft is difficult to occur, and a single elastic bending primary vibration 1)/ is directly generated at the rotational speed Nl' (frequency E1').

Of course, the design must be such that this critical rotational speed N1' is removed from the operating range.

On the other hand, in the case of this embodiment, the first spring constant has a smaller spring constant at both ends. Since it is soft (supported by the second elastic body 62, 70), rigid body vibration Q such as translational motion or pitching first occurs in the low rotation (low frequency) region (rotation speed N01 frequency f,), and then , through the so-called mass region of this rigid body vibration, an elastic bending primary vibration P is generated at a rotational speed N, (frequency f,).

The above-mentioned mass region is a region where the self-aligning action of the propeller shaft main body 12 is obtained, and by exerting the self-aligning action in this way, even if an unbalance amount exists in the propeller shaft 10 more than necessary, , the center of the rotational axis is automatically shifted to the main axis with the maximum moment of inertia for balance adjustment, achieving stable rotational motion.

Furthermore, since the mass region where the above-mentioned self-aligning effect can be obtained largely occupies the practical rotation region, a significant vibration reduction effect can be obtained.

Furthermore, in the elastic bending primary vibration P, since both ends of the propeller shaft body 12 approach the free support condition, the first
The next vibration P is shifted to the high frequency side.

Therefore, the dangerous rotational speed that appears due to the primary vibration P of the elastic surface can be shifted to a higher frequency side, making it possible to extend the practical rotational range to higher speeds and increasing the allowable rotational speed. You will be able to do so.

Although the vibration will be exacerbated in the region of the rigid body vibration Q, by tuning the rigid body vibration Q to the lowest possible frequency range, the presence of rigid body resonance in the normal use range can be avoided. Since the rigid body vibration Q is in a low rotational speed range, the excitation force level is small.

That is, in the propeller shaft lO of this embodiment, it is possible to create a rigid body vibration in the low rotational speed range where the excitation force is as small as possible, to allow this vibration to pass through in a short time, and to use the mass range in the practical range. Desirably, this makes it possible to prevent vibrations from worsening even when the rotational speed increases, and to prevent vibrations from worsening even if the mass imbalance increases slightly, and further,
The margin for the critical rotational speed increases, making it possible to increase the rotational speed.

In the manufacturing stage of the propeller shaft 10, it is possible to reduce the quality control of the product, and it is possible to achieve a significant cost reduction.

In addition, in the propeller shaft IO of this embodiment, the first shaft IO has a small spring constant. Since it is supported via the second elastic body 62, 70, it has a vibration isolation effect against vibration phenomena input to the vehicle body from the rear suspension system due to power plant and power train vibrations such as acceleration noise. Obtainable.

Further, in the propeller shaft 10 of this embodiment, the front and rear joint members 14.16 are connected to the first outer race 20.20a and the 27th outer race 22.20a.
22a and the inner race 24.24a can be easily moved relative to each other in the axial direction via the ball 32, so even when the suspension is moved up and down under torque, the propeller Since the length of the shaft IO can be adjusted easily, it is possible to prevent twisting that occurs in conventional simple spline connections.

FIG. 4 shows another embodiment of the present invention, in which the same components as those in the above embodiment are denoted by the same reference numerals and the explanation thereof will be omitted.

In explaining this embodiment, only the front joint member 14 will be explained in this embodiment, since the front joint member and the rear joint member have substantially the same structure in their essential parts.

That is, the main difference between this embodiment and the above embodiment is that the front joint member 58 is eliminated and the propeller shaft IO side end of the second outer race 22 is extended in the direction of the first outer race 20. In this extended portion 80, the first
The first outer race 20 is supported on the inner circumference of the extended portion 80 via an annular elastic body 82 that surrounds the outer circumferential direction of the outer race 20 .

Incidentally, the second outer race 22 on which the extended portion 80 is formed is supported by the extensicon 56 via the bearing 64 as in the above embodiment, and as a result, the end of the propeller shaft body 12 is It is rotatably supported by the vehicle body via the elastic body 82.

Therefore, even in this embodiment, the propeller shaft body 1
Since the restraining force during the translational movement of 2 is significantly reduced, the same effect as in the above embodiment can be achieved.

Furthermore, in this embodiment, "C" is the first outer lace 2.
Since the first outer race 20 and the second outer race 22 are rotated together, only the elastic body 82 is provided between the first outer race 20 and the extended portion 80. Since there is no need to provide a bearing and a joint case, the number of parts can be significantly reduced, and the joint part can thus be made smaller, lighter, and simpler.

It goes without saying that the structure of this embodiment can also be applied to a rear joint member.

Incidentally, in each of the above embodiments, explanations have been given taking a two-joint type propeller shaft as an example, but the present invention is not limited to this, and the present invention can be applied to other types such as a 3 m, hand J% Ij propeller shaft, etc. It goes without saying that it can be done.

Further, in each of the above embodiments, two first . Second elastic body 62.
70 and these elastic bodies 62 and 70 are arranged at both ends of the propeller shaft body 12, but the invention is not limited to this, and the propeller shaft body 12 can be connected to the vehicle body side via at least one elastic body. By supporting the propeller shaft body 12 at °C, the function of the present invention, that is, the self-aligning effect can be enjoyed. Needless to say, it is okay.

As described in detail, in the vehicle propeller shaft of the present invention, in claim 1, a joint member movable in a translational direction is disposed between the propeller shaft body, the power plant, and the final reduction gear. Since the propeller shaft body is configured such that at least one portion of the propeller shaft body is supported by the vehicle body via an elastic body,
The binding force of the joint member in the translational direction is small;
Since no torque is applied to the elastic body that supports the propeller shaft body, the spring constant of the elastic body can be set to a significantly small value, and the translational movement of the propeller shaft body can be suppressed. It can be done easily.

Therefore, when a self-aligning action is applied to the propeller shaft body during high-speed rotation, the propeller shaft body is easily displaced in the translational direction and automatically moved in the direction that achieves rotational balance, greatly reducing vibration generation. reduced.

This eliminates the need for extremely high balance accuracy on the propeller shaft, making it possible to significantly improve productivity and reduce product costs, as well as increasing the critical rotational speed of the propeller shaft itself. This makes it possible to increase the rotation speed and, in turn, greatly improve the reliability of the propeller shaft.

According to a second aspect of the invention, the joint member includes a pair of first joint members disposed facing each other. a second connecting member; and the first connecting member. an intermediate member disposed between the second connecting members; Since the second connecting member and the intermediate member are each locked in the rotational direction, the first connecting member and the intermediate member are connected to each other through the intermediate member. Torque transmission is possible between the second connecting members, and by extension, between the propeller shaft body, the power plant, and the final reduction gear, and the first connecting member. Since the second connecting member and the intermediate member are connected in a tiltable manner through the low-friction member, the low-friction member significantly reduces the friction brim and restraining force during the translational movement of the propeller shaft body. can do.

Therefore, by configuring the joint member in this way, it is possible to transmit a large torque, and the restraining force on displacement in the translational direction can be made extremely small. It has the excellent effect of being able to smoothly perform self-alignment of the propeller shaft body while exhibiting durability.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
3 is an explanatory diagram showing the vibration characteristics of the propeller shaft according to the present invention in comparison with a conventional one; FIG.
The figure is an enlarged sectional view of a main part showing another embodiment of the present invention, and FIG. 5 is a sectional view showing a conventional propeller shaft. lO... Propeller shaft, 12... Propeller shaft body, 14... Front rear 9 India member, 16...
... Rear joint member, 20.20a... First outer race (first connection member), 22, 22a... Second
7 Outer lace (second connection member), 24°248...
Inner race (intermediate member), 28, 30... groove,
32... Ball (low friction member), 44... Transmission, 50... Final M speed device, 62... First elastic body, 70... Second elastic body, 82... Elasticity body. 3 other people

Claims (2)

[Claims] (1) The propeller shaft body is connected to the output shaft of the power plant and the input shaft of the final reduction gear via a joint member that is movable in the translational direction and has a torque transmission function, and the propeller shaft body A propeller shaft for a vehicle, characterized in that at least one portion of the shaft is supported on a vehicle body side via an elastic body. (2) The joint member includes a pair of first and second connecting members arranged to face each other, and an intermediate member arranged between the first and second connecting members, and the first and second connecting members The propeller shaft for a vehicle according to claim 1, wherein the propeller shaft and the intermediate member are respectively locked in the rotational direction and connected so as to be tiltable via a low-friction member. .