JP2004232758A - Propeller shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a propeller shaft having a shock absorption part formed simply and accurately and assuring a stable performance of shock absorption. <P>SOLUTION: The propeller shaft 10 is equipped with an outer shaft 20 and an inner shaft 21 which are put in spline fitting with each other and has a shock absorption part 30 to couple the shafts 20 and 21 together in such a way as capable of contracting with an impact load, wherein the shock absorption part 30 is structured so that a supporting member 31 is fitted by pressure in the outer shaft 20 and the end face of the inner shaft 21 is abutted to the supporting member 31 in the contracting direction with respect to the outer shaft 20. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a propeller shaft of a vehicle.
[0002]
[Prior art]
Patent Documents 1 and 2 disclose propeller shafts that absorb an impact load due to a vehicle collision or the like.
[0003]
The propeller shaft of Patent Document 1 has an outer shaft and an inner shaft that are spline-fitted to each other, and the tip of the inner shaft is caulked at the extension of the outer shaft. When an excessive impact load due to a collision or the like is applied, the caulked portion is plastically deformed, and the tip of the inner shaft comes out of the caulked portion, whereby the inner shaft and the outer shaft are contracted, and the impact load is absorbed and relaxed in this process.
[0004]
The propeller shaft of Patent Document 2 has an outer shaft and an inner shaft which are spline-fitted to each other, and a taper portion formed at a free end of the inner shaft is axially fitted to a taper portion of an inner periphery of the outer shaft. It was done. When an excessive impact load due to a collision or the like is applied, the inner shaft and the outer shaft are contracted by disengagement of the tapered portion in the axial direction, and the impact load is absorbed and reduced in this process.
[0005]
[Patent Document 1]
JP-A-11-303846 ([0021], [0022], FIG. 1)
[0006]
[Patent Document 2]
JP-A-7-305715 ([0011], [0014], FIG. 1)
[0007]
[Problems to be solved by the invention]
In the propeller shaft of Patent Document 1, the impact absorbing portion is formed by caulking the tip of the outer shaft, and the processing is complicated and cost increases.
[0008]
In the propeller shaft of Patent Document 2, although the axial fitting portion (tapered portion) of the inner shaft to the outer shaft is provided at its free end, the propeller shaft is member-integral with the spline portion, and the outer shaft is The influence of the play in the rotational direction of the spline fitting of the inner shaft and the inner shaft affects this axial fitting portion. For this reason, the fitting strength of the axial fitting portion between the outer shaft and the inner shaft cannot be set with high accuracy over a long period of time with respect to an impact load.
[0009]
SUMMARY OF THE INVENTION An object of the present invention is to provide a propeller shaft that easily and accurately constitutes a shock absorbing portion and stabilizes shock absorbing performance.
[0010]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a propeller shaft having a shock absorbing portion that connects an outer shaft and an inner shaft that are spline-fitted to each other so as to be contractable by an impact load, wherein the shock absorbing portion has an inner diameter of the outer shaft. The support member is press-fitted, and the end surface of the inner shaft is brought into contact with the support member in the contraction direction with respect to the outer shaft.
[0011]
According to a second aspect of the present invention, in the first aspect, the outer shaft has a smaller spline portion than a press-fit inner diameter portion for a support member, and a step portion is provided between the press-fit inner diameter portion and the spline portion, A retaining ring engaged with an end of the inner shaft is locked to the step.
[0012]
According to a third aspect of the present invention, in the first or second aspect of the present invention, a plurality of the shock absorbing portions are further arranged in the axial direction.
[0013]
The support member may have any form as long as it is press-fitted into the inner diameter of the outer shaft, such as an annular collar or a disk.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
1 is a plan view showing a propeller shaft, FIG. 2 is an enlarged view showing a main part of FIG. 1 partially cut away, FIG. 3 is a sectional view showing a first shock absorbing part, and FIG. FIG.
[0015]
As shown in FIG. 1, a propeller shaft 10 of an automobile includes two shaft members divided into a front shaft 11 and a rear shaft 12, and the two shafts 11 and 12 are connected by a universal joint 13. The front end of the front shaft 11 is connected via a universal joint 14 to a connection yoke 15 connected to an output shaft of a transmission on the engine side. The rear end of the rear shaft 12 is connected via a universal joint 16 to a connection yoke 17 connected to a differential gear. A second inner shaft 22 of the front shaft 11, which will be described later, is supported by the center bracket 19 via the center bearing 18 and the rubber-like elastic member 18A.
[0016]
The propeller shaft 10 includes first and second shock absorbers 30 and 40 juxtaposed in the axial direction of an intermediate portion of the front shaft 11 in order to absorb an impact load due to a collision or the like. That is, the front shaft 11 can spline-fit each of the first inner shaft 21 and the second inner shaft 22 to both ends of the hollow outer shaft 20, and can contract the outer shaft 20 and the first inner shaft 21 by an impact load. And a second shock absorber 40 that connects the outer shaft 20 and the second inner shaft 22 so that they can be contracted by an impact load as follows.
[0017]
As shown in FIG. 2, the outer shaft 20 has a first sleeve 20B welded to one end of a steel pipe 20A, a second sleeve 20C welded to the other end of the steel pipe 20A, and a first sleeve 20B and a second sleeve 20C. The spline teeth 20D and 20E extending in the axial direction are formed on the inner peripheral surface of the spline. The first inner shaft 21 has one end 21A as a mounting portion for the universal joint 14, the other end 21B as a hollow shaft portion, and spline teeth 21C extending in the axial direction formed on the outer peripheral surface of the other end 21B. The spline teeth 21C are lightly pressed into the spline teeth 20D of the first sleeve 20B, and are spline-fitted. One end 22A of the second inner shaft 22 is used as an inner shaft mounting portion of the universal joint (constant velocity joint) 13, and spline teeth 22C extending in the axial direction are formed on the outer peripheral surface of the other end 22B. The spline teeth 22C are lightly pressed into the spline teeth 20E of the second sleeve 20C and are spline-fitted.
[0018]
(First Shock Absorber 30) (FIG. 3)
The first shock absorbing portion 30 press-fits the outer periphery of the support member 31 made of an annular collar into the press-fit inner diameter portion 20F provided on the first sleeve 20B at one end of the outer shaft 20, and fixes the end face of the first inner shaft 21 to the outer shaft. The support member 31 is brought into contact with the end surface of the support member 31 in a contraction direction relative to the support member 20 (a direction in which the first inner shaft 21 enters and absorbs the hollow portion of the outer shaft 20; a rightward direction in FIG. 3).
[0019]
The first sleeve 20B at one end of the outer shaft 20 has a smaller spline tooth 20D than the press-fit inner diameter portion 20F for the support member 31 and has an annular stepped portion 20G between the press-fit inner diameter portion 20F and the spline tooth 20D. Then, the retaining ring 32 engaged with the annular groove 21D provided on the outer end side of the other end 21B of the first inner shaft 21 with respect to the spline teeth 21C is locked to the step portion 20G. At this time, the support member 31 presses against the end face of the first inner shaft 21 in the extending direction with respect to the outer shaft 20, and presses and holds the retaining ring 32 engaged with the annular groove 21D of the first inner shaft 21 against the step portion 20G. I do. As a result, the outer shaft 20 and the first inner shaft 21 are integrally assembled without any play in the axial direction, and a projecting position (assembly position) of the first inner shaft 21 with respect to the outer shaft 20 is determined.
[0020]
The procedure for assembling the first shock absorbing section 30 is as follows.
(1) The spline teeth 20D provided on the first sleeve 20B of the outer shaft 20 and the spline teeth 21C provided on the other end 21B of the first inner shaft 21 are lightly pressed. The outer shaft 20 and the first inner shaft 21 are slid (shortened) in the axial direction until the annular groove 21D of the first inner shaft 21 projects outward, and the retaining ring 32 is engaged with the annular groove 21D.
[0021]
(2) The outer shaft 20 and the first inner shaft 21 are moved in the axial direction until the retaining ring 32 engaged with the first inner shaft 21 abuts on the stepped portion 20G of the first sleeve 20B of the outer shaft 20 and is locked. Slide (extend). Thereby, the projecting position (assembly position) of the first inner shaft 21 with respect to the outer shaft 20 is determined.
[0022]
(3) The support member 31 is press-fitted into the press-fit inner diameter portion 20F of the first sleeve 20B of the outer shaft 20. At this time, the end surface of the first inner shaft 21 and the end surface of the support member 31 are brought into contact with each other while ensuring that the retaining ring 32 is locked to the step portion 20G of the first sleeve 20B.
(4) One end of the steel pipe 20A is welded to the first sleeve 20B of the outer shaft 20.
[0023]
(Second Shock Absorber 40) (FIG. 4)
The second shock absorbing portion 40 press-fits the outer periphery of the support member 41 made of an annular collar into the press-fitting inner diameter portion 20H provided on the second sleeve 20C at the other end of the outer shaft 20, and moves the end face of the second inner shaft 22 outward. The support member 41 is brought into contact with the end surface of the support member 41 in a contraction direction with respect to the shaft 20 (a direction in which the second inner shaft 22 enters the hollow portion of the outer shaft 20 and contracts, that is, a leftward direction in FIG. 4).
[0024]
The second sleeve 20C at the other end of the outer shaft 20 has a smaller spline tooth 20E than the press-fit inner diameter portion 20H for the support member 41, and has an annular stepped portion 201 between the press-fit inner diameter portion 20H and the spline tooth 20E. Then, the retaining ring 42 engaged with the annular groove 22D provided on the side of the outer end side of the other end 22B of the second inner shaft 22 with respect to the spline teeth 22C is locked to the stepped portion 20I. At this time, the support member 41 presses against the end face of the second inner shaft 22 in the direction of extension with respect to the outer shaft 20, and presses and holds the retaining ring 42 engaged with the annular groove 22D of the second inner shaft 22 against the stepped portion 20I. I do. As a result, the outer shaft 20 and the second inner shaft 22 are integrally assembled without any play in the axial direction, and the projecting position (assembly position) of the second inner shaft 22 with respect to the outer shaft 20 is determined.
[0025]
The procedure for assembling the second shock absorber 40 is as follows.
(1) The spline teeth 20E provided on the second sleeve 20C of the outer shaft 20 and the spline teeth 22C provided on the other end 22B of the second inner shaft 22 are lightly pressed. The outer shaft 20 and the second inner shaft 22 are slid (shortened) in the axial direction until the annular groove 22D of the second inner shaft 22 projects outward, and the retaining ring 42 is engaged with the annular groove 22D.
[0026]
(2) The outer shaft 20 and the second inner shaft 22 are moved in the axial direction until the retaining ring 42 engaged with the second inner shaft 22 abuts on the stepped portion 201 of the second sleeve 20C of the outer shaft 20 and is locked. Slide (extend). Thereby, the projecting position (assembly position) of the second inner shaft 22 with respect to the outer shaft 20 is determined.
[0027]
(3) The support member 41 is press-fitted into the press-fit inner diameter portion 20H of the second sleeve 20C of the outer shaft 20. At this time, the end surface of the second inner shaft 22 and the end surface of the support member 41 are brought into contact with each other while ensuring that the retaining ring 42 is locked to the stepped portion 201 of the second sleeve 20C.
(4) The other end of the steel pipe 20A is welded to the second sleeve 20C of the outer shaft 20.
[0028]
Next, the operation of the propeller shaft 10 will be described.
When an impact load acts on the engine after deforming a crushable zone such as an engine room of the vehicle body from the front of the vehicle, the impact load is transmitted from the transmission to the front shaft 11 of the propeller shaft 10 and the first shaft 11 The shock absorbing portion 30 and the second shock absorbing portion 40 absorb and mitigate the absorption sequentially.
[0029]
That is, in the first shock absorbing portion 30, the shock load releases the spline engagement between the spline teeth 20D of the first sleeve 20B of the outer shaft 20 and the spline teeth 21C of the other end 21B of the first inner shaft 21. Then, the support member 31 press-fitted into the press-fit inner diameter portion 20F of the first sleeve 20B of the outer shaft 20 is pulled out, and the other end 21B of the first inner shaft 21 is made to enter the inside of the steel pipe 20A of the outer shaft 20. And the first inner shaft 21 is relatively contracted. The impact load is efficiently absorbed and alleviated by the energy for removing the support member 31 from the press-fit inner diameter portion 20F of the first sleeve 20B and the relative displacement thereof. The movement of the first inner shaft 21 is stopped when the stopper portion (flange) 21E (FIG. 1) on the one end 21A side of the first inner shaft 21 contacts the end surface of the first sleeve 20B of the outer shaft 20.
[0030]
If the impact load cannot be completely absorbed by the first impact absorbing portion 30, the stopper portion 21 </ b> E on the one end 21 </ b> A side of the first inner shaft 21 abuts on the end surface of the first sleeve 20 </ b> B of the outer shaft 20, and the impact load is reduced. Extends through the outer shaft 20 to the side of the second shock absorbing portion 40, and the second shock absorbing portion 40 further absorbs a shock load in the same manner as the first shock absorbing portion 30. That is, the impact load releases the spline engagement between the spline teeth 20E of the second sleeve 20C of the outer shaft 20 and the spline teeth 22C of the other end 22B of the second inner shaft 22, and press-fits the second sleeve 20C of the outer shaft 20. The support member 41 press-fitted into the inner diameter portion 20H is pulled out and removed, the other end 22B of the second inner shaft 22 enters the inside of the steel pipe 20A of the outer shaft 20, and the outer shaft 20 and the second inner shaft 22 are relatively contracted. . At this time, the steel pipe 20A of the outer shaft 20 and the second sleeve 20C penetrate the rubber-like elastic member 18A of the center bracket 19 and move. The impact load is efficiently absorbed and mitigated by the energy for removing the support member 41 from the press-fit inner diameter portion 20H of the second sleeve 20C and the relative displacement thereof. The movement of the outer shaft 20 is stopped when the end surface of the second sleeve 20C of the outer shaft 20 comes into contact with the stopper 22E (FIG. 1) on the one end 22A side of the second inner shaft 22.
[0031]
In the shock absorbing units 30 and 40, the press-fitting strength of the support members 31 and 41 with respect to the impact load is set to such an extent that a reference impact that is fatal to the occupant of the cabin is not generated when the impact load is input.
[0032]
According to the present embodiment, the following operation and effect can be obtained.
(Operation and Effect Corresponding to Claim 1)
{Circle around (1)} Since the shock absorbing portions 30 and 40 are configured by press-fitting the support members 31 and 41 into the inner diameter of the outer shaft 20, the processing and assembly can be simplified and the cost can be reduced.
[0033]
{Circle around (2)} The support members 31 and 41 press-fitted into the outer shaft 20 are separate from the inner shafts 21 and 22, and the influence of the play in the rotation direction of the spline fitting between the outer shaft 20 and the inner shafts 21 and 22 is affected. It does not extend to the press-fit portions of the support members 31 and 41. For this reason, the press-fitting strength of the support members 31 and 41 with respect to the outer shaft 20 can be set with high accuracy with respect to an impact load.
[0034]
(Operation and Effect Corresponding to Claim 2)
{Circle around (3)} The retaining rings 32, 42 abutting the end surfaces of the inner shafts 21, 22 against the support members 31, 41 in the contraction direction with respect to the outer shaft 20, and engaging with the end portions of the inner shafts 21, 22 by the outer ring 20. At the steps 20G and 20I between the press-fit inner diameter portions 20F and 20H of the support members 31 and 41 and the spline teeth 20D and 20E. Therefore, while preventing the inner shafts 21 and 22 from coming off with respect to the outer shaft 20, the projecting positions of the inner shafts 21 and 22 with respect to the outer shaft 20 are determined, and the movement amount of the inner shafts 21 and 22 when absorbing the shock (impact Absorption stroke).
[0035]
(Operation and Effect Corresponding to Claim 3)
{Circle around (4)} By arranging the plurality of shock absorbing portions 30 and 40 in the axial direction, the shock load can be sequentially absorbed by the respective shock absorbing portions 30 and 40, and the shock absorbing performance of the propeller shaft 10 can be improved.
[0036]
As described above, the embodiment of the present invention has been described with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like that do not depart from the gist of the present invention. Are also included in the present invention.
[0037]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, in a propeller shaft, a shock-absorbing part can be comprised easily and with high precision, and the impact-absorbing performance can be stabilized.
[Brief description of the drawings]
FIG. 1 is a plan view showing a propeller shaft.
FIG. 2 is an enlarged view showing a main part of FIG. 1 with a part cut away.
FIG. 3 is a cross-sectional view showing a first shock absorber.
FIG. 4 is a cross-sectional view showing a second shock absorber.
[Explanation of symbols]
Reference Signs List 10 propeller shaft 20 outer shaft 20D, 20E spline teeth 20F, 20H press-fit inner diameter portion 20G, 201 step portion 21, 22 inner shaft 30, 40 shock absorbing portion 31, 41 support member 32, 42 retaining ring

Claims (3)

In a propeller shaft having a shock absorbing portion that connects the outer shaft and the inner shaft that are spline-fitted to each other so as to be contractable by an impact load,
The propeller shaft, wherein the shock absorbing portion press-fits the support member into the inner diameter of the outer shaft and abuts the end surface of the inner shaft on the support member in a contraction direction with respect to the outer shaft. The outer shaft has a smaller spline portion than the press-fit inner diameter portion for the support member, and a step portion is provided between the press-fit inner diameter portion and the spline portion,
The propeller shaft according to claim 1, wherein a retaining ring engaged with an end of the inner shaft is locked to the step portion. The propeller shaft according to claim 1, wherein a plurality of the shock absorbing portions are arranged side by side in the axial direction.

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