JP2010169213A - Vehicular power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular power transmission device having rotary members integrally constituted by press-fitting spline teeth to each other, in which gear noise is reduced. <P>SOLUTION: A clearance 30 is formed in a part of a tooth face press-fitting section of spline teeth 26, 28 of a first rotary member 18 and a second rotary member 22 interacting each other when a counter driven gear sub-assembly 14 is rotated to one side. The connection rigidity of the first rotary member 18 and second rotary member 22 is thereby made different according to deceleration and acceleration of a vehicle, and a resonance frequency is made different according to the deceleration and acceleration of the vehicle. The gear noise is then reduced by shifting the resonance frequency from a peak point of a gear noise waveform in either deceleration or acceleration. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a vehicular power transmission device having a rotating member integrally formed by press-fitting splines formed on a first rotating member and a second rotating member that function as a part of a gear mechanism. In particular, the present invention relates to gear noise reduction of a gear mechanism.

  A vehicular power transmission device having a rotating member that is integrally formed by press-fitting splines formed on a first rotating member and a second rotating member that function as a part of a gear mechanism is well known. ing. FIG. 6 is a view showing only a part of a state in which a plurality of spline teeth formed on the first rotating member 100 and the second rotating member 102 are press-fitted together. As shown in FIG. 6, both inclined surfaces 106 of the spline teeth 104 of the first rotating member 100 and the inclined surfaces of the spline teeth 108 of the second rotating member 102 are press-fitted. FIG. 6 shows only a state in which some spline teeth are fitted, but in actuality, each spline tooth is fitted as described above.

JP 2004-168249 A

  By the way, since the first rotating member and the second rotating member function as a part of the gear mechanism, it is preferable to reduce gear noise generated from the gear mechanism. Usually, the gear noise has different noise waveforms depending on acceleration and deceleration of the vehicle, and is generated in a region (frequency) where the peak of the gear noise varies depending on the acceleration and deceleration.

  FIG. 4 is a diagram showing the relationship between the frequency characteristic of the gear mechanism and the gear noise waveform. In FIG. 4, the solid line indicates the deceleration noise waveform when the vehicle is decelerated, and the broken line indicates the acceleration noise waveform when the vehicle is accelerated. As shown in FIG. 4, peak points at which gear noise is maximum occur in different frequency regions during vehicle acceleration and deceleration. Here, as shown in FIG. 4, when the peak point A of the deceleration noise waveform at the time of deceleration of the vehicle and the resonance frequency C of the gear mechanism overlap, the gear noise at the peak point A of the deceleration noise waveform is reduced. It is desirable to shift the resonant frequency of the mechanism to a different frequency. However, if the resonance frequency of the gear mechanism is shifted to the frequency region D, there is a problem that the acceleration noise deteriorates because it overlaps the peak point B of the acceleration noise waveform during vehicle acceleration. Normally, the resonance frequency of the gear mechanism is constant regardless of the acceleration and deceleration of the vehicle, but by changing the resonance frequency of the gear mechanism to a different frequency according to the acceleration and deceleration of the vehicle, the acceleration noise waveform and the deceleration are reduced. There has been a need for a technique for reducing gear noise by preventing the peak point of the noise waveform and the resonance frequency from overlapping.

  On the other hand, as disclosed in Patent Document 1, in the connecting portion between the inner pipe and the outer pipe of the propeller shaft of the vehicle, the rubber having different thicknesses in the forward direction and the reverse direction on both sides of the spline tooth surface. It becomes possible to change the resonance frequency of the gear system by interposing the material. However, in Patent Document 1, there is a problem in that the manufacturing process is complicated and the number of parts is increased, for example, rubber materials having different thicknesses are required depending on the rotation direction of the propeller shaft.

  The present invention has been made against the background of the above circumstances, and the object of the present invention is that splines formed on the first rotating member and the second rotating member functioning as part of the gear mechanism are mutually connected. In a vehicle power transmission device having a rotating member that is integrally formed by press-fitting, the resonance frequency of the gear mechanism is easily changed according to the acceleration and deceleration of the vehicle, so that the vehicle is accelerated and decelerated. An object of the present invention is to provide a vehicle power transmission device that can reduce gear noise.

  To achieve the above object, the gist of the invention according to claim 1 is that (a) the splines formed on the first rotating member and the second rotating member functioning as part of the gear mechanism are press-fitted together. (B) the first rotating member and the second rotating member that receive a reaction force when rotating the rotating member in any one direction; A gap is formed in a part of the tooth surface press-fitting portion of the spline teeth of the member.

  According to the vehicle power transmission device of the first aspect of the present invention, the tooth surface of the spline teeth of the first rotating member and the second rotating member that receive a reaction force with each other when the rotating member rotates in one direction. Since a gap is formed in a part of the press-fitting portion, the coupling rigidity of the first rotating member and the second rotating member can be made different according to deceleration and acceleration of the vehicle, and according to deceleration and acceleration of the vehicle. The resonance frequency can be made different. Therefore, by appropriately setting the resonance frequency, the gear noise can be reduced by shifting the resonance frequency from the peak point of the gear noise waveform in both deceleration and acceleration.

It is sectional drawing explaining the structure of the counter driven gear sub-assembly which is a part of gear mechanism in the power transmission device with which this invention was applied. It is the arrow line view which looked at the spline press injection part shown in FIG. 1 from the arrow A side. It is the elements on larger scale which expanded the area | region shown with a broken line in FIG. It is a figure which shows the relationship between the frequency characteristic of a gear mechanism, and a gear noise waveform. FIG. 3 is another partial enlarged view in which a region indicated by a broken line in FIG. 2 is enlarged. It is a figure which shows only the state in which the spline teeth currently formed in the conventional 1st rotation member and the 2nd rotation member were fitted by mutually press-fitting.

  Here, preferably, the gap formed in a part of the tooth surface press-fitting portion of the spline teeth is a peak point of acceleration noise and a peak point of deceleration noise generated from the gear mechanism during acceleration and deceleration of the vehicle. The resonance frequency of the gear mechanism is set so as not to overlap. In this way, the magnitude of the peak point of acceleration noise and the peak point of deceleration noise can be suppressed, and gear noise can be suppressed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a cross-sectional view illustrating the structure of a counter driven gear sub-assembly 14 (corresponding to a rotating member of the present invention) that is a part of a gear mechanism 12 in a vehicle power transmission device 10 to which the present invention is applied. The counter driven gear sub-assembly 14 includes a first rotating member 18 having a drive pinion gear 16 and a second rotating member 22 having a driven gear 20. The spline teeth 26 formed on the outer peripheral surface of the first rotating member 18 and the spline teeth 28 formed on the inner peripheral surface of the second rotating member 22 are press-fitted in a state of being fitted to each other. Thus, the counter driven gear sub-assembly 14 is integrally formed. The counter driven gear sub-assembly 14 is used, for example, to transmit a driving force transmitted from a drive gear (not shown) meshing with the driven gear 20 to a differential ring gear (not shown) meshing with the drive pinion gear 16.

  2 is an arrow view of the spline press-fit portion 24 shown in FIG. 1 as viewed from the arrow A side. As shown in FIG. 2, a plurality of spline teeth 26 are formed on the outer peripheral surface of the first rotating member 18, and the spline teeth 26 corresponding to the portions indicated by “◯” have a wide tooth width. It is press-fitted in the radial direction (large-diameter press-fitting part). A plurality of spline teeth 28 are formed on the inner peripheral surface of the second rotating member 22 so as to be fitted to the spline teeth 26 formed on the first rotating member 18. The spline teeth 26 and 28 are press-fitted together to prevent movement in the axial direction. Further, in the spline press-fit portion 24 indicated by “Δ”, the spline teeth 26 are press-fitted by the tooth surfaces of the spline teeth 26 and the spline teeth 28 (tooth surface press-fit portion 32). Note that the spline press-fitting portion 24 indicated by “Δ” is not press-fitted in the radial direction.

  FIG. 3 is a partially enlarged view in which a region indicated by a broken line in FIG. 2 is enlarged. As shown in the drawing, in the tooth surface press-fitting portion 32 of the spline teeth 26 and 28 indicated by “Δ” in FIG. 2, the distance between the adjacent spline teeth 28 of the second rotating member 22 is increased, so One side of the tooth surface press-fitting portion 32 of the spline teeth 26 and the spline teeth 28 is missing and a gap 30 is formed. As shown in FIG. 3, the gap 30 is formed on the clockwise direction side (one side). Similarly, in the tooth surface press-fitting portion 32 indicated by “Δ” shown in FIG. It is formed on (one side). Note that the gap 30 is formed only in the portion indicated by “Δ” in FIG. 2, and therefore the gap 30 is not formed in the portion of the other spline press-fitting portion 24. Therefore, even if the gap 30 is formed, the first rotating member 18 and the second rotating member 22 do not rotate relative to each other.

  When the spline press-fit portion 24 is configured as described above, for example, if the second rotating member 22 is rotated in the direction of arrow a in FIG. 2 during vehicle acceleration, the spline teeth on the side shown in FIG. Since the tooth surface press-fit portions 32 of 26 and 28 are normally press-fitted, they receive a reaction force with each other. Therefore, at the time of vehicle acceleration, the first rotating member 18 and the second rotating member 22 obtain normal coupling rigidity. On the other hand, if the second rotating member 22 is rotated in the direction of arrow b (one direction) in FIG. 2 during vehicle deceleration, the spline teeth 26 on the side shown in FIG. 28, the tooth surface press-fit portions 32 receive a reaction force with each other. In this embodiment, a portion of the tooth surface press-fit portion 32 that receives the reaction force is shown in FIG. Since one side (d) is not toothed and the gap 30 is formed, the coupling rigidity between the first rotating member 18 and the second rotating member 22 is lower than that during acceleration.

  Therefore, the coupling rigidity of the first rotating member 18 and the second rotating member 22 differs between when the vehicle is accelerated and when the vehicle is decelerated. Here, when the coupling rigidity is different as described above, the resonance frequency of the gear mechanism 12 changes accordingly during acceleration and deceleration. Accordingly, for example, by changing the resonance frequency at the time of vehicle deceleration in FIG. 4 from the frequency region C to D, the peak of the deceleration noise and the resonance frequency can be shifted. The value can be lowered. On the other hand, at the time of vehicle acceleration, by maintaining the resonance frequency in the frequency region C, an increase in the value of the peak point B of acceleration noise during acceleration indicated by a broken line can be suppressed. Note that the specific tuning of the resonance frequency is based on the noise waveforms during vehicle acceleration and deceleration, so that the peak point of each noise waveform and the resonance frequency of the gear mechanism 12 do not overlap each other. Or set analytically.

  Here, in FIG. 3, the distance between the adjacent spline teeth 28 of the second rotating member 22 is increased, so that one side of the tooth surface press-fitting portion 32 of the spline teeth 28 of the press-fitted spline teeth 26 is missing. As shown in FIG. 5, the gap 30 may be formed by cutting one side of the spline teeth 26 of the first rotating member 18 and partially cutting the teeth. Absent. Even in such a configuration, the spline teeth 26 and 28 are normally press-fitted on one side in the rotational direction of the spline press-fitting portion 24, while the gap 30 is formed on the other side. The coupling rigidity of the first rotating member 18 and the second rotating member 22 can be changed during acceleration and deceleration of the vehicle. Therefore, the resonance frequency of the gear mechanism 12 can be made different when the vehicle is decelerating and accelerating based on the change in the coupling rigidity, and the peak point of the noise waveform that is different during both acceleration and deceleration. Overlapping with the resonance frequency can be avoided, and gear noise can be reduced.

  As described above, according to this embodiment, the tooth surfaces of the spline teeth 26 and 28 of the first rotating member 18 and the second rotating member 22 that interact with each other when rotating to either one side of the counter driven gear sub-assembly 14. Since a gap 30 is formed in a part of the vehicle, the coupling rigidity of the first rotating member 18 and the second rotating member 22 can be made different according to the deceleration and acceleration of the vehicle. Accordingly, the resonance frequency can be made different. Therefore, by appropriately setting the resonance frequency, the gear noise can be reduced by shifting the resonance frequency from the peak point of the gear noise waveform in both deceleration and acceleration.

  Further, according to the present embodiment, the gap 30 formed in a part of the tooth surface press-fitting portion 32 of the spline teeth 26 and 28 has a peak of acceleration noise generated from the gear mechanism 21 during acceleration and deceleration of the vehicle. The point and the peak point of the deceleration noise are set so that the resonance frequency of the gear mechanism 12 does not overlap. In this way, the magnitude of the peak point of acceleration noise and the peak point of deceleration noise can be suppressed, and gear noise can be suppressed.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the present invention is applied to the counter driven gear sub-assembly 14, but the present invention is not limited to the counter-driven gear sub assembly 14, and may be appropriately applied to any rotating member having a gear mechanism. can do.

  In the above-described embodiment, the gap 30 is formed on the clockwise side of the spline teeth 26, but the above is an example, and the rotation of the first rotating member 18 and the second rotating member 22 during acceleration and deceleration is performed. Depending on the direction, gear noise waveform, resonance frequency, etc., it may be formed counterclockwise.

  Further, in the above-described embodiment, the gap 30 is formed in a part of the tooth surface press-fitting portion 32 on the side receiving the reaction force when the vehicle is decelerated. However, the gap 30 is not limited to the decelerating side. A gap 30 may be formed in a part of the tooth surface press-fitting portion 32 on the side receiving the reaction force.

  Further, in the above-described embodiment, six gaps 30 are formed at equal angular intervals as indicated by “Δ” in FIG. 2, but the number of gaps and the number of gaps formed depending on, for example, tuning of the resonance frequency. The position to be changed is appropriately changed.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Power transmission device for vehicle 12: Gear mechanism 14: Counter driven gear sub-assembly (rotating member)
18: First rotating member 22: Second rotating member 26: Spline teeth 28: Spline teeth 30: Gap 32: Tooth surface press-fitting portion

Claims (1)

A vehicular power transmission device having a rotating member integrally formed by press-fitting spline teeth formed on a first rotating member and a second rotating member that function as a part of a gear mechanism,
A gap is formed in a part of the tooth surface press-fitting portion of the spline teeth of the first rotating member and the second rotating member that receive a reaction force when rotating in any one direction of the rotating member. A vehicle power transmission device.

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