JPS639795Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a noise prevention device in an automobile drive system that transmits driving force from an engine to wheels via a transmission, a power transmission shaft, a final reduction mechanism, etc.

For example, in the case of a front engine/rear drive or four-wheel drive vehicle, the driving force from the engine 1 is transferred to the clutch 2, as shown in FIG.
The power is transmitted to wheels 8 and 9 via a transmission 3, power transmission shafts (hereinafter referred to as propeller shafts) 4 and 5, final reduction mechanisms 6 and 7, and the like.
In such a drive system, rotational fluctuations caused by torque fluctuations of the engine 1 cause noise due to gear meshing in the transmission 3, final reduction mechanisms 6, 7, etc., and furthermore, noise is generated in the propeller shafts 4, 5. Noise is generated due to resonance of torsional vibration.

As a method for reducing such noise, it is known that an effective method is to attach an inertial mass (mass damper) to a portion of the drive string to increase the moment of inertia during power transmission.

For example, as a noise prevention device such as the one mentioned above,
There is one disclosed in the -56944 publication. As shown in FIG. 2, a mass damper 14 that rotates integrally is attached to the drive pinion shaft 13 of the final reduction mechanism 12, which is connected to the universal joint 11 provided at the end of the propeller shaft 10.
Noise is prevented by increasing the moment of inertia of No. 3. This prior art example is intended to prevent noise such as gear meshing noise particularly related to the final reduction mechanism 12 in the drive system.

On the other hand, when a four-wheel-drive vehicle was driven with all four wheels driven, the transmission 3 generated noise due to the meshing sound of gears. This is caused by engine torque fluctuations between the input side gear connected to the front wheel drive propeller shaft 4 via a universal joint and the sleeve that meshes with the input side gear and transmits the driving force from the engine 1. It is something that occurs.

Such noise can be eliminated by applying the above-mentioned prior art, but the propeller shaft 4 penetrates into the case of the transmission 3 and final reduction mechanism 6 via universal joints at both ends. It is rotatably supported by the gearbox, and is spline-coupled with the corresponding drive shaft to absorb fluctuations in the relative distance between the transmission 3 and the final reduction mechanism 6, so that dust and the like do not enter from the outside through the penetrating portion of each case. The problem is that a dust cover must be provided, and the number of parts increases along with the installation of the mass damper, which increases the number of assembly steps.

This invention is an improvement in view of the above-mentioned problems in the drive system of an automobile. That is, this invention provides a power transmission shaft that penetrates a case such as a transmission or a final reduction mechanism and is rotatably supported, and is provided with a mass damper that covers the end of the part that passes through the case. To provide a noise prevention device which has both noise prevention and dustproof effects with a small number of parts.

An embodiment of this invention will be described below with reference to the drawings.

Figure 3 is a diagram showing the structure of the power distribution section of the transmission in a four-wheel drive vehicle. In the figure, 15 is the case of the transmission, and 16 is the output shaft to which the driving force from the engine is transmitted via the clutch. The provided drive gear 17 is a driven shaft that transmits power to the rear wheels,
It is rotatably supported in the case 15 by a bearing 18. Reference numeral 19 denotes a driven gear formed integrally with the driven shaft 17, and is constantly meshed with the drive gear 16.
Transmits power to rear wheels (not shown). Reference numeral 20 denotes a flange member fitted to a rear spline 21 formed on the driven shaft 17, to which a rear wheel drive propeller shaft (not shown) is attached via a universal joint. Reference numeral 22 denotes a sleeve that is slidably spline-coupled to the front spline 23 formed on the driven shaft 17, and a switching shaft (not shown) for switching between rear-wheel drive and four-wheel drive is fitted on the outer peripheral surface. An annular groove 24 is formed. An output shaft 25 is mounted on the tip of the driven shaft 17 via a bearing 26, and its outer periphery is rotatably supported by the case 15 via the bearing 27. At the rear end of this output shaft 25 is the driven shaft 17.
facing the front spline 23 of the sleeve 2
forming a transmission gear 28 spline-fitted with 2;
A male spline 29 is formed on the front shaft portion 25a. 30 is a yoke of a universal joint 37 attached to the end of the propeller shaft 36 that transmits power to the front wheels, and the rear cylindrical portion 31 penetrates the case 15;
It is rotatably and slidably supported in the case 15 by a bimetal form bush 32 in the axial direction. Further, a female spline 33 is formed on the inner circumferential surface of the cylindrical portion 31 to fit the spline 29 of the output shaft 25.
A is spline-fitted to allow variation in the relative distance between the transmission and the final reduction mechanism to transmit rotational force. 34 is an oil seal that prevents grease from leaking between the case 15 and the yoke 30. Reference numeral 35 denotes a dust cover and mass damper integrally attached to the outer circumference of the yoke 30, which can sufficiently cover the end face of the penetrating portion of the case 15 and the space between the case 15 and the yoke 30, regardless of the fluctuation of the yoke 30 in the axial direction. It is formed in a long length to prevent dust etc. from entering from outside. Also, the mass damper 35 has a thick wall and its inertial mass is increased to increase the moment of inertia of the yoke 30 and propeller shaft during power transmission, thereby suppressing various noises.

To explain its function in the above configuration, when the sleeve 22 is located on the front spline 23 of the driven shaft 17 and is not engaged with the transmission gear 28 of the output shaft 25, the driving force from the engine is transferred from the driving gear 16. It is transmitted to the driven shaft 17 via the driven gear 19, and from the driven shaft 17 to the rear wheels via the propeller shaft, and the vehicle travels with rear wheel drive.

Also, the sleeve 22 is moved along the front spline 23, and the sleeve 22 is moved along the front spline 23 and the output shaft 2.
When it straddles both sides and meshes with the transmission gear 28 of No. 5,
The driving force from the engine is transmitted from the drive gear 16 to the driven shaft 17 via the driven gear 19, from the driven shaft 17 on one side via the propeller shaft to the rear wheels, and on the other hand to the front part of the driven shaft 17. Power is transmitted to the output shaft 25 via the spline 23, sleeve 22, and transmission gear 28, from the output shaft 25 to the yoke 30, and further to the propeller shaft 3.
The power is transmitted to the front wheels through 6, allowing the vehicle to travel with all-wheel drive.

When this four-wheel drive is running, the mass damper 3 attached to the yoke 30 is installed in the drive system on the front wheel drive side.
5 rotates together to increase the moment of inertia of the propeller shaft 36 and yoke 30, so even if rotational fluctuations occur due to engine torque fluctuations, the sleeve 22 and the transmission gear 28, through which power is transmitted, are meshed. The propeller shaft 3
6 torsional vibration etc. can also be suppressed. Furthermore, mass damper 3
5 covers the space between the yoke 30 and the case 15, and prevents dust and the like from entering from the outside.

In the above embodiment, the mass damper 35 is provided at the end of the propeller shaft connected to the transmission side, but it may also be provided at the connecting portion on the final reduction mechanism side.

As explained above, this invention applies to the drive system that transmits the driving force from the engine to the wheels via the transmission, power transmission shaft, final reduction mechanism, etc.
Since a mass damper is provided on the outer periphery of the power transmission shaft that is rotatably supported through the case and covers the end of the penetration part of the case, the moment of inertia of the power transmission shaft is increased and the gears in the drive system are Noise caused by meshing noise and torsional vibration can be prevented. In addition, the mass damper covers the case penetration part through which the power transmission shaft passes.
It also serves as a dust cover to prevent dust from entering from the outside, reducing the number of parts and making assembly easier.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view showing the drive system of an automobile, Fig. 2 is a sectional view showing a conventional example of a final reduction mechanism equipped with a mass damper, and Fig. 3 shows an embodiment of the noise prevention device according to the present invention. FIG. 15...Transmission case, 16...Drive gear,
17... Driven gear, 22... Sleeve, 25...
Output shaft, 28...Transmission gear, 29...Spline, 30...Yoke, 31...Cylinder part, 33...Spline 35...Dust cover and mass damper, 3
6...Propeller shaft, 37...Universal joint.

Claims (1)

[Scope of utility model registration request] In a drive system that transmits driving force from an engine to wheels via a transmission, a power transmission shaft, a final reduction mechanism, etc., the case is attached to the outer periphery of the power transmission shaft that is rotatably supported through the case. A noise prevention device for a drive system of an automobile, characterized in that a mass damper is provided to cover an end of a penetrating portion of the vehicle.