JP2005201325A - Noise reduction device for transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise reduction device for a transmission capable of realizing the optimization of the reduction of an idling noise level. <P>SOLUTION: The elastic constant k1 and hysteresis H1 in a region of a first stage of the side with a small torsional angle θCL in the region of two-stage torsional characteristics of a buffering mechanism, which is provided to a clutch, are respectively set smaller than the elastic constant k2 and hysteresis H2 in a region of a second stage of the side with a large torsional angle θCL. When an idle gear is disengaged from an output shaft and in an idling state during the idle rotation of an internal combustion engine, the actual torsional angle θCL of the clutch is in the region of the second stage of the side with a large torsional angle exceeding prescribed torsional angles θ1, θ1' by the viscosity resistance of the lubricating oil if the lubricating oil of a gear is in the temperature range of below a prescribed low temperature (for example, 25°C). While, the actual torsional angle θCL of the clutch is set so as to be within the region of the first stage if the lubricating oil of the gear is in the temperature range larger than the prescribed low temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a transmission noise reduction device, and more particularly to a technique for reducing idle noise.

Transmission idle noise is caused by the fact that combustion in each cylinder of the engine is discontinuous and torque fluctuations occur. Gears between the drive shaft gear and the driven shaft gear, between the driven shaft gear and the idle gear, etc. It is said that the tooth surface separation and tooth beat occur repeatedly in the meantime.
Therefore, conventionally, when a backlash removal mechanism is not installed between the drive shaft gear and the driven shaft gear, the tooth surface separation and gearing between the drive shaft gear and the driven shaft gear should be considered. Thus, the idle noise is calculated and predicted, and the idle noise is reduced by adjusting the multistage characteristic (spring constant) of the multistage buffer mechanism (spring) provided in the clutch.

For example, the greater the gear force between gears, the larger the gear teeth and the more idle noise, so the clutch operating angle during idling is set so that the spring constant is not applied to the second stage where the spring constant is high and the gear force is large. A technique has been developed that reduces idle noise by restraining to a low first stage (in the first stage region) (see Patent Document 1).
Japanese Patent Laid-Open No. 11-344048

However, as a result of recent research, even if the clutch operating angle is suppressed to the first stage having a low spring constant as shown in Patent Document 1, the idle noise level actually increases as the oil temperature of the lubricating oil increases. It has been confirmed that there is a phenomenon that.
This phenomenon is considered to be because the viscous resistance of the lubricating oil decreases as the oil temperature rises, and the tooth striking force between the gears increases due to so-called backlash nonlinear resonance.

This phenomenon can occur in the same manner even when a backlash removing mechanism is mounted between the drive shaft gear and the driven shaft gear, which is not preferable.
The present invention has been made to solve such problems, and an object of the present invention is to provide a transmission noise reduction device that optimizes the reduction of the idle noise level.

  In order to achieve the above-described object, the transmission noise reduction device according to claim 1 is provided between the internal combustion engine and the input shaft of the transmission which can achieve the shift by switching the meshing state of the plurality of gears. A drive of an internal combustion engine which is provided around the output shaft of the transmission so as to constitute a part of the plurality of gears and is detachable from the output shaft, and is transmitted through the input shaft. In a noise reduction device for a transmission, comprising: a freewheeling gear capable of connecting and disconnecting force by engagement / disengagement with the output shaft, wherein the clutch includes a buffering mechanism that absorbs torque fluctuations of the internal combustion engine. Has at least two stages of torsional characteristics with different elastic constants and hysteresis of the torsional torque with a predetermined torsional angle as a threshold with respect to the torsional angle of the clutch due to the torque fluctuation. Twist The elastic constant and hysteresis of the first stage region on the smaller angle side are set smaller than the elastic constant and hysteresis of the second stage region on the larger torsion angle side, respectively, and during idling of the internal combustion engine, When the idler gear is detached from the output shaft and is in an idle state, the actual torsion angle of the clutch is set to the predetermined value due to the viscous resistance of the lubricating oil in a range where the lubricating oil of the gear is below a predetermined low temperature. While the torsion angle is applied to the second stage region on the larger torsion angle side, the actual torsion angle of the clutch is within the first stage region when the lubricating oil of the gear is greater than a predetermined low temperature. It is characterized by being set to fit in.

  According to the transmission noise reduction device of claim 1, the elastic constant and hysteresis of the first stage region on the side with the smaller torsion angle among the two-stage torsional characteristics of the buffer mechanism provided in the clutch are respectively The elastic constant and hysteresis of the second stage region on the larger torsion angle side are set smaller than the hysteresis constant, and the idle gear is detached from the output shaft during idle rotation of the internal combustion engine. In the range where the gear lubricant is below a predetermined low temperature, the actual torsional angle of the clutch exceeds the predetermined torsional angle due to the viscous resistance of the lubricant and is applied to the second stage region on the larger torsional angle. Since the actual torsion angle of the clutch is set so as to be within the first stage region when the oil is larger than a predetermined low temperature, the elastic constant and hysteresis of the first stage region are the predetermined values for the lubricating oil. Below the low temperature of Therefore, the actual torsion angle of the clutch is set to be small enough to be applied to the second stage region due to the torque fluctuation of the idling rotation of the internal combustion engine. When the lubricating oil is below a predetermined low temperature, the actual torsion angle is Although the noise associated with the meshing of the plurality of gears of the transmission is slightly increased by being applied to the second stage region having a larger elastic constant and hysteresis than the first stage region, a buffer mechanism is provided when the lubricating oil is higher than a predetermined low temperature. As a result, torque fluctuations of the internal combustion engine are satisfactorily absorbed, and the striking force generated between the plurality of gears can be kept small.

As a result, compared with the case where the elastic constant and hysteresis of the first step region are set so that the actual torsion angle of the clutch is within the first step region, the noise level can be suppressed sufficiently low. It is possible to reduce idle noise during idling of the internal combustion engine as a whole regardless of the oil temperature of the oil, and optimization of idle noise level reduction can be achieved.
Preferably, the elastic constant and the torsional torque hysteresis of the first stage region on the side with a smaller torsion angle in the two-stage torsional characteristics region, respectively, are obtained when the idler gear outputs the output during idle rotation of the internal combustion engine. The noise level associated with the meshing of the plurality of gears when the actual torsion angle is applied to the second-stage region when detached from the shaft and in the idle state is independent of the temperature of the lubricating oil. When the elastic constant and hysteresis of the first step region are set so that the actual torsion angle of the clutch is within the first step region, the noise level is lower than the noise level in the normal temperature region of the lubricant. It should be set as follows.

  As a result, even if the actual torsion angle is applied to the second step region when the lubricating oil is below a predetermined low temperature, the first step is performed so that the actual torsion angle of the clutch is within the first step region. Compared with the case where the elastic constant and hysteresis of the region are set, the noise level as a whole can be surely kept low.

Embodiments of a noise reduction device for a transmission according to the present invention will be described below with reference to the accompanying drawings.
Referring to FIG. 1, there is shown a schematic configuration diagram of a noise reduction device for a transmission according to the present invention mounted on a vehicle. The transmission shown in FIG. 1 can achieve shifting by switching the meshing state of the gear on the counter shaft and the plurality of idle gears in the actual machine, but here, for convenience, the transmission of the actual machine is used. It is configured as a transmission model in which all the idle gears on the internal output shaft are removed and the inertia moments of all the idle gears are equivalently concentrated on the third speed idle gear portion of the transmission. However, the idle noise reduction technique in the transmission model described below can be applied to an actual machine as it is.

  As shown in the figure, a transmission (transmission, hereinafter abbreviated as T / M) 1 has an input shaft 2, a counter shaft 8, and an output shaft 14 rotatably supported on a casing 3. Each of the shaft 8 and the output shaft 14 is provided with a gear so that a driving force from an engine (not shown) is transmitted from the input shaft 2 through the counter shaft 8 to the output shaft 14.

  More specifically, a clutch 4 is provided at one end of the input shaft 2 outside the casing 3, and a drive shaft gear 6 is provided at the other end so as to be able to rotate synchronously with the input shaft 2. The counter shaft 8 is provided with a driven shaft gear 10 that meshes with the drive shaft gear 6, and a driven shaft gear 12 is provided so as to be able to rotate synchronously with the counter shaft 8. The output shaft 14 is provided with an idle gear 16 that meshes with the driven shaft gear 12.

The driven shaft gear 10 is provided with a backlash removing mechanism 11, thereby preventing backlash of the driven shaft gear 10, and noise caused by rattling between the driving shaft gear 6 and the driven shaft gear 10. Is prevented as much as possible.
The idle gear 16 is rotatable about the output shaft 14 and can be engaged / disengaged with the output shaft 14, and is configured to be engaged / disengaged manually or automatically according to a driving force disconnection instruction or a shift instruction from the driver. ing. For example, when the engine is in an idle operation state and the shift selection position of T / M1 is in the neutral stage, the idle gear 16 is detached from the output shaft 14 and idles around the output shaft 14, The engine output is not transmitted to the output shaft 14. Note that the idle gear 16 is conventionally known in transmissions, and a detailed description of its configuration is omitted here.

  The clutch 4 is provided with a buffer mechanism 5 comprising, for example, a plurality of coil springs and disc springs, etc., and this buffer mechanism 5 absorbs engine torque fluctuations and eliminates abnormal noise in the drive system. The That is, the buffer mechanism 5 is configured as a multi-stage buffer mechanism having a multi-stage torsional characteristic, that is, a clutch characteristic, so that the engine driving force is smoothly supplied from the flywheel 20 via the clutch 4 regardless of the engine rotational speed Ne. To T / M1.

Specifically, the clutch characteristics are set in two stages, and as shown in FIG. 2, the buffer mechanism 5 has two types of coil springs 5a, 5b and a hysteresis mechanism 5c capable of varying the hysteresis H of the clutch torque (torsion torque) according to the spring constant k.
That is, referring to FIG. 3, the clutch characteristic, that is, the relationship between the torsion angle θCL of the clutch 4 and the clutch torque TCL, which is the reaction force of the buffer mechanism 5, is shown. The clutch characteristic is defined by the spring constant k and the hysteresis H. However, as shown in the figure, in the first stage region where the torsion angle θCL is small from θ1 ′ to θ1 (predetermined torsion angle) (θ1 ′ <θCL <θ1), the spring constant k of the corresponding coil spring 5a is In the second stage region (θCL ≦ θ1 ′, θ1 ≦ θCL) where the hysteresis H is set to be as small as k1 and the hysteresis H of the hysteresis mechanism 5c is also small as H1, the spring constant k of the corresponding coil spring 5b is k2. And the hysteresis H of the hysteresis mechanism 5c is set to be as large as H2 (H1 <H2).

  More specifically, the lubricating oil in T / M1 has a higher viscous resistance acting on the clutch 4 as the oil temperature is lower, and when the viscous resistance is larger, the center of the torsion angle θCL of the clutch 4 is positive as seen in FIG. The clutch characteristic in the first stage region, that is, the first stage spring constant k1 and hysteresis H1, indicates that the engine is in an idle operation state and the idle gear 16 is When the oil temperature is not more than a predetermined low temperature (for example, 25 ° C.) and the viscosity resistance of the lubricating oil is large when the oil is detached from the output shaft 14 and swings around the output shaft 14, the torque fluctuation of the engine The actual torsion angle θCL of the clutch 4 is applied to the second stage region exceeding θ1 ′ and θ1 while the actual torsion angle θCL is not applied to the second stage region when the oil temperature is higher than the predetermined low temperature. Is set to be relatively small

  Further, when the engine is in an idle operation state and the idle gear 16 is detached from the output shaft 14 and idles around the output shaft 14, the torsion angle θCL of the clutch 4 is in the first stage region. However, between the driven shaft gear 12 and the idler gear 16, the viscosity resistance of the lubricating oil decreases as the temperature of the lubricating oil increases, and so-called backlash nonlinear resonance increases the tooth striking force between the gears. There is a tendency that the noise due to tooth separation and tooth catching, i.e., idle noise, increases (see JSME Vol.35, No.1, etc.). Since the larger the larger, the larger the spring constant k1 and the hysteresis H1 of the first stage are set so as to satisfy the requirement to be applied to the region of the second stage and to minimize the tooth hitting force.

Specifically, the spring constant k1 and the hysteresis H1 are the ratios of the spring constants k1 and k10 of the coil spring 5a corresponding to the first stage region when the reference spring constant is k10 and the reference hysteresis is H10. For example, k1 / k10 = 0.4, and the ratio of the hysteresis H1 and H10 of the hysteresis mechanism 5c is set to be, for example, H1 / H10 = 1.0.
Hereinafter, the operation of the noise reduction device for a transmission according to the present invention configured as described above, that is, the clutch 4 when the engine is in an idle operation state and the idle gear 16 is idle around the output shaft 14 will be described. The idle noise reduction action will be described.

  When the clutch characteristics of the clutch 4, that is, the spring constant k and the hysteresis H are set to be relatively small as k1 and H1 in the first stage region and relatively large as k2 and H2 in the second stage region as described above, When the oil temperature of the lubricating oil in T / M1 is equal to or lower than the predetermined low temperature, the center of the torsion angle θCL of the clutch 4 is positive as seen in FIG. Shifting in the (+) direction, the torsion angle θCL of the clutch 4 due to engine torque fluctuation is applied to the second stage region.

  Thus, when the torsion angle θCL of the clutch 4 is applied to the second stage region, the spring constant k and hysteresis H are relatively large, k2 and H2, in the second stage region. 1/2 sub-harmonic vibration and 1/3 sub-harmonic vibration are generated, and the tooth striking force between the gears is increased, and noise due to tooth surface separation and tooth striking, that is, idle noise tends to increase (automotive technology). (See Proceedings Vol.35, No.1, etc.)

  That is, referring to FIG. 4, the relationship between the oil temperature (T / M oil temperature) of the lubricating oil in the T / M1 and the tooth hitting force FGA and the idle noise level in the clutch 4 having the clutch characteristics set as described above. (Solid line ■ mark) is shown based on the experiment, but when the oil temperature is below a predetermined low temperature (for example, 25 ° C.), the tooth striking force FGA is relatively large and proportional to this. As a result, idle noise increases to some extent.

However, when the oil temperature of the lubricating oil is higher than the predetermined low temperature, the viscosity resistance of the lubricating oil becomes small as described above, and therefore the center of the twist angle θCL of the clutch 4 that has been shifted is seen in FIG. Thus, the torsion angle θCL of the clutch 4 due to engine torque fluctuation is within the first stage region without being applied to the second stage region.
Thus, when the torsion angle θCL of the clutch 4 is not applied to the second stage region and falls within the first stage region, 1/2 subharmonic vibration and 1/3 subharmonic vibration no longer occur. In a region where the temperature is higher than a predetermined low temperature (for example, 25 ° C.), as shown in FIG. 4, the tooth striking force between the gears is small, and the idle noise is small.

On the other hand, even when the torsion angle θCL of the clutch 4 is within the first stage region, as described above, the viscosity resistance of the lubricating oil increases as the temperature of the lubricating oil increases between the driven shaft gear 12 and the idler gear 16. Therefore, the so-called backlash nonlinear resonance tends to increase the tooth hitting force between the gears and increase the idle noise.
However, here, the clutch characteristics of the clutch 4, that is, the spring constant k and the hysteresis H are k1 and H1 (for example, k1 / k10 = 0.4, H1 / H10 = 1. 0) is set to a small value, the gear force due to the backlash nonlinear resonance becomes extremely small, and the increase in idle noise can be minimized.

  That is, FIG. 4 shows that the ratcheting force due to the backlash nonlinear resonance is compared with the case where the clutch characteristics in the first stage region are set to be, for example, k1 / k10 = 0.4 and H1 / H10 = 1.0. When the spring constant k1 is large and k1 / k10 = 1.0 (dotted line ▲) so that the torsion angle θCL during idle operation is within the first stage area while minimizing the FGA, it is also during idle operation. Combined with the case where the spring constant k1 is increased to k1 / k10 = 1.0 and the hysteresis H1 is increased to H1 / H10 = 1.5 so that the torsion angle θCL falls within the first stage region (dotted line ●). As shown, by setting the spring constant k1 and hysteresis H1 in the first stage region to be small, for example, k1 / k10 = 0.4, H1 / H10 = 1.0 (solid line ■ mark) In the range where the oil temperature is higher than the predetermined low temperature, the twist angle θCL is It is possible to suppress the tooth striking force FGA, and hence the idle noise level, much smaller than when it falls within the range (broken line ▲ mark, broken line ● mark).

  As described above, the clutch characteristics in the first stage region, that is, the spring constant k1 and the hysteresis H1 are set small so that the torsion angle θCL of the clutch 4 is applied to the second step region when the oil temperature is below a predetermined low temperature. As a result, compared with the case where the clutch characteristic of the first stage region is set so that the torsion angle θCL during idle operation falls within the first stage region, the gear striking force FGA, that is, the idle noise level is generally reduced. It is possible to optimize the reduction of the idle noise level.

  Further, according to FIG. 4, when the clutch characteristics are set so that, for example, k1 / k10 = 0.4 and H1 / H10 = 1.0, the oil temperature is within a predetermined low temperature range as described above. The tooth force FGA becomes relatively large due to the 1/2 subharmonic vibration and the 1/3 subharmonic vibration, and idle noise increases to some extent during idle operation. The maximum value of the idle noise level is set when the spring constant k is set large and k1 / k10 = 1.0 so that the torsion angle θCL is within the first stage region while minimizing the rattling force FGA due to the non-linear resonance. It is smaller than the tooth striking force FGA, that is, the idle noise level, in the T / M1 normal temperature range (for example, 60 ° C. or more) indicated by the broken line ▲.

  In other words, the torsion of the clutch 4 is set by setting the spring constant k1 and the hysteresis H1 in the first step region to be, for example, k1 / k10 = 0.4 and H1 / H10 = 1.0. The spring constant k is such that the maximum value of the idle noise level when the angle θCL is applied to the second stage region is such that the torsion angle θCL is within the first stage region while minimizing the tooth striking force FGA due to the backlash nonlinear resonance. Is set to be smaller than the idle noise level in the normal temperature range of T / M1 (for example, 60 ° C. or higher) when k1 / k10 = 1.0 (broken line ▲). The spring constant k1 and the hysteresis H1 are set.

As a result, the tooth striking force FGA, that is, the idle noise level can be reliably lowered as a whole, for example, can be suppressed to an allowable level or less (see FIG. 4).
In particular, considering that the oil temperature of the T / M1 lubricating oil is often in the normal temperature range during or after the vehicle travels, the 1/2 subharmonic in the range where the oil temperature is below a predetermined low temperature. Even if the tooth striking force FGA increases due to vibration or 1/3 subharmonic vibration, and the idle noise level temporarily increases, there is almost no concern, as described above. By setting the clutch characteristics, idle noise can be reduced extremely effectively.

Although the description of the embodiment of the noise reduction device for a transmission according to the present invention is finished above, the embodiment is not limited to the above.
For example, in the above embodiment, the clutch characteristic of the clutch 4 is configured in two stages, but the clutch characteristic may be three or more stages. In this case, the clutch characteristic in at least the first stage region is set as described above. Thus, the same effect as described above can be obtained.

In the above embodiment, the spring constant k1 and the hysteresis H1 in the first stage region are set to be, for example, k1 / k10 = 0.4 and H1 / H10 = 1.0. The hysteresis H1 may be set to an optimum value without departing from the gist of the present invention.
In the above embodiment, the backlash removing mechanism 11 is provided. However, the present invention can be suitably applied without the backlash removing mechanism.

1 is a schematic configuration diagram of a noise reduction device for a transmission according to the present invention mounted on a vehicle. It is a figure which shows the semicircle part of a clutch in layers. It is a figure which shows the clutch characteristic, ie, the relationship between the torsion angle θCL of the clutch and the clutch torque TCL. It is a figure which shows the relationship between the oil temperature (T / M oil temperature) of lubricating oil, and tooth | gear force FGA, Comprising: It is a figure explaining the effect of this invention.

Explanation of symbols

1 T / M (transmission)
2 Input shaft 4 Clutch 5 Buffer mechanism 5a, 5b Coil spring 5c Hysteresis mechanism 8 Counter shaft 11 Backlash removing mechanism 12 Driven shaft gear 14 Output shaft 16 Free-wheeling gear

Claims (1)

A clutch provided between an internal combustion engine and an input shaft of a transmission that is shifted by switching meshing states of the plurality of gears, and an output shaft of the transmission so as to constitute a part of the plurality of gears An idler gear provided so as to be rotatable around and capable of being engaged with and disengaged from the output shaft, and capable of connecting and disconnecting the driving force of the internal combustion engine transmitted through the input shaft by engagement and disengagement with the output shaft; In a noise reduction device for a transmission having a buffer mechanism for absorbing torque fluctuations of an internal combustion engine in the clutch,
The buffer mechanism has at least two stages of torsion characteristic regions in which the elastic constant and the hysteresis of the torsion torque are different from each other with a predetermined torsion angle as a threshold with respect to the torsion angle of the clutch due to the torque fluctuation,
Among the two-stage torsional characteristic areas, the elastic constant and hysteresis of the first-stage area on the smaller twist angle side are:
Each is set smaller than the elastic constant and hysteresis of the second step region on the larger torsion angle side,
During idle rotation of the internal combustion engine, when the idle gear is detached from the output shaft and is in an idle state, the lubricating oil of the gear is in a range of a predetermined low temperature or less due to the viscous resistance of the lubricant. While the actual torsion angle exceeds the predetermined torsion angle and is applied to the second stage region on the larger torsion angle side, the actual torsion angle of the clutch is within the range where the lubricating oil of the gear is greater than a predetermined low temperature. A noise reduction device for a transmission, wherein the transmission noise reduction device is set to be within the first stage region.

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