JP2020131854A - Vibration reduction device - Google Patents

Abstract

To adjust a vibration characteristics in a power transmission path for transmitting power to drive a vehicle to a vibration characteristic corresponding to a travel state of the vehicle.SOLUTION: An engagement mechanism 50 selectively causes a first interim shaft 31 to engage with a second interim shaft 32 or an output shaft 20. The engagement mechanism 50 realizes a first engagement state where the first interim shaft 31 engages with the output 20 and a second engagement state where the first interim shaft 31 engages with the second interim shaft 32. The vibration reduction device 100 realizes a vibration characteristic corresponding to a travel state of a vehicle by selectively utilizing the first engagement state and the second engagement state according to the travel state of the vehicle.SELECTED DRAWING: Figure 2

Description

The present invention relates to a vibration reducing device.

Patent Document 1 describes a torque fluctuation absorbing device that absorbs fluctuation torque of an internal combustion engine in a hybrid vehicle. The torque fluctuation absorbing device of Patent Document 1 can absorb the fluctuation torque of the internal combustion engine by the first elastic member and the second elastic member having a higher torsional rigidity than the first elastic member, and the torsional rigidity of the first elastic member is It is set so that the internal combustion engine can absorb the fluctuation torque of the internal combustion engine when generating a generator.

Patent Document 2 describes a torque converter having a lock-up mechanism that directly connects the pump impeller side and the turbine runner side so as to be connectable and detachable. The torque converter of Patent Document 2 variably controls the damper rigidity at the time of lockup by the lockup mechanism according to the number of operating cylinders of the engine.

Japanese Unexamined Patent Publication No. 2003-278836 Japanese Unexamined Patent Publication No. 2016-142404

For example, as described in Patent Documents 1 and 2, a device for reducing vibration in a power transmission path that transmits power for driving a vehicle is known. For example, by reducing the spring constant of the spring mechanism that has the role of absorbing vibration, the amplitude of vibration generated in the power transmission path can be reduced. However, if the spring constant of the spring mechanism that absorbs vibration is reduced, it may not be possible to transmit power quickly within the power transmission path, which may reduce the response performance of the vehicle during acceleration, for example. There is.

An object of the present invention is to make the damping characteristic of vibration in the power transmission path that transmits the power for driving the vehicle a damping characteristic according to the traveling state of the vehicle.

The vibration reduction device, which is one of the specific examples of the present invention, is a vibration reduction device that reduces vibration in the power transmission path that transmits the power for driving the vehicle from the input side to the output side, and is one of the input sides. It has an engaging mechanism that changes the damping characteristics of vibration in the power transmission path by selectively engaging one of the plurality of output-side shafts with the shaft, and the traveling state of the vehicle. By selecting one axis on the output side that is engaged with one axis on the input side according to the above, the damping characteristic of vibration in the power transmission path is set to the damping characteristic according to the traveling state of the vehicle. It is characterized by doing.

For example, the engaging mechanism selectively engages one of the plurality of shafts on the output side with one shaft on the input side to change the spring constant in the power transmission path. , The damping characteristic of the vibration in the power transmission path may be changed.

Further, for example, the vibration reducing device includes an input shaft into which power obtained from the power source of the vehicle is input, a first intermediate shaft connected to the input shaft via a first spring, and the engaging mechanism. The second intermediate shaft is selectively engaged with the first intermediate shaft, and the second intermediate shaft is connected to the second intermediate shaft via a second spring, and is connected to the first intermediate shaft by the engaging mechanism. It may have an output shaft that is selectively engaged. Then, the engaging mechanism may be, for example, a dual clutch type engaging mechanism that selectively engages the second intermediate shaft or the output shaft with the first intermediate shaft.

Further, for example, when it is determined that the traveling state of the vehicle is in the accelerating state, the vibration reducing device engages the first intermediate shaft with the output shaft by the engaging mechanism to perform the input. When the power transmission path for transmitting power from the shaft to the output shaft via the first spring and the first intermediate shaft is formed and it is determined that the traveling state of the vehicle is in a non-accelerated state, the engagement is performed. By engaging the first intermediate shaft with the second intermediate shaft by the coupling mechanism, the first spring, the first intermediate shaft, the second intermediate shaft, and the second spring are inserted from the input shaft. The power transmission path for transmitting power to the output shaft may be formed.

Further, for example, the vibration reducing device engages the first intermediate shaft with the output shaft by the engaging mechanism, so that the output from the input shaft via the first spring and the first intermediate shaft The power transmission path for transmitting power to the shaft may be formed, and the vibration of the power transmission path may be absorbed by the second spring and the second intermediate shaft connected to the output shaft.

According to one of the specific examples of the present invention, the damping characteristic of vibration in the power transmission path that transmits the power for driving the vehicle becomes the damping characteristic according to the traveling state of the vehicle.

It is a figure which shows the specific example of the vehicle equipped with the vibration reduction device. It is a figure which shows the specific example of the vibration reduction apparatus. It is a figure for demonstrating the 1st engagement state. It is a figure for demonstrating the 2nd engagement state. It is a figure which shows the specific example of the damping characteristic of vibration. It is a figure which shows the specific example 1 of the control according to the traveling state of a vehicle. It is a figure which shows the specific example 2 of the control according to the traveling state of a vehicle.

FIG. 1 is a diagram showing an example of a specific embodiment of the present invention. FIG. 1 shows a specific example of a vehicle equipped with the vibration reduction device 100. The vibration reduction device 100 is mounted on a vehicle such as an automobile, and can be used to reduce torsional vibration generated in a transmission path that transmits power for driving the vehicle.

In the specific example shown in FIG. 1, the vehicle uses, for example, an engine (internal combustion engine) as the power source 200, and the power output from the power source 200 is transmitted to the drive shaft 400 via the transmission 300, and the wheels (tires). Rotate and run.

In the specific example shown in FIG. 1, the vibration reduction device 100 is arranged between the power source 200 and the transmission 300. The vibration reducing device 100 reduces the vibration generated in the power transmission system from the power source 200 to the drive shaft 400, for example, in order to improve the riding comfort of the vehicle. If the vibration generated in the power transmission system can be reduced by the vibration reduction device 100, the power transmission by the conventionally known fluid coupling can be reduced, and the power from the engine can be transmitted to the drive shaft 400 in a state of being directly connected by the mechanical element. For example, improvement of fuel efficiency is expected.

FIG. 2 is a diagram showing a specific example of the vibration reduction device 100. FIG. 2 shows a specific example of the vibration reduction device 100 mounted on the vehicle shown in FIG. The vibration reduction device 100 shown in FIG. 2 includes an input shaft 10, an output shaft 20, a first intermediate shaft 31, a second intermediate shaft 32, and an engaging mechanism 50.

In the specific example shown in FIG. 2, the power obtained from the power source 200 (FIG. 1) of the vehicle is input to the input shaft 10. A first intermediate shaft 31 is connected to the input shaft 10 via a first spring 41. Further, the second intermediate shaft 32 is selectively engaged with the first intermediate shaft 31 by the engaging mechanism 50. An output shaft 20 is connected to the second intermediate shaft 32 via a second spring 42. Further, the output shaft 20 is selectively engaged with the first intermediate shaft 31 by the engaging mechanism 50. Then, power is transmitted from the output shaft 20 to the output side of the vehicle (for example, the transmission 300 in FIG. 1).

The engagement mechanism 50 selectively engages one of the plurality of axes on the output side with one axis on the input side, thereby causing vibration in the power transmission path of the vehicle illustrated in FIG. 1, for example. Change the damping characteristics.

In the specific example shown in FIG. 2, the engagement mechanism 50 is a dual clutch type engagement mechanism that selectively engages the output side second intermediate shaft 32 or the output shaft 20 with the input side first intermediate shaft 31. .. Then, the engaging mechanism 50 realizes a first engaging state in which the first intermediate shaft 31 and the output shaft 20 are engaged and a second engaging state in which the first intermediate shaft 31 and the second intermediate shaft 32 are engaged. Will be done.

By the way, if the mechanism (device) for realizing the first engaging state and the mechanism (device) for realizing the second engaging state are separately provided to form the engaging mechanism 50, the shaft length is extended and vibration is reduced. There is a possibility that the mountability of the device 100 on the vehicle will deteriorate. On the other hand, if the engaging mechanism 50 is a dual clutch type engaging mechanism, it is possible to share a part (preferably many members) of the mechanism that realizes the first engaging state and the second engaging state. Therefore, for example, the elongation of the shaft length is minimized, and the mountability of the vibration reducing device 100 on the vehicle is improved.

FIG. 3 is a diagram for explaining a first engagement state. FIG. 3 shows a specific example of the first engagement state realized by the vibration reduction device 100 of FIG. In the first engaging state, the engaging mechanism 50 engages the first intermediate shaft 31 and the output shaft 20. For example, the engaging mechanism 50 mechanically connects the first intermediate shaft 31 and the output shaft 20. In the first engaging state, the first intermediate shaft 31 and the second intermediate shaft 32 are not engaged by the engaging mechanism 50.

Therefore, in the first engaged state, a path for transmitting power from the input shaft 10 to the output shaft 20 via the first spring 41 and the first intermediate shaft 31 is formed, for example, as illustrated in FIG. In the first engaged state, only the first spring 41 of the first spring 41 and the second spring 42 intervenes in the power transmission system from the input shaft 10 to the output shaft 20, and the second engagement described later The rigidity of the power transmission system is higher than that in the combined state. Therefore, in the first engaged state, power can be transmitted from the input shaft 10 to the output shaft 20 more quickly than in the second engaged state.

Further, in the vibration reducing device 100 of the specific example shown in FIG. 2, as illustrated in FIG. 3, the second intermediate shaft 32 is connected to the output shaft 20 via the second spring 42. Therefore, in the first engagement state realized by the vibration reduction device 100 of FIG. 2, the second spring 42 and the second intermediate shaft 32 are generated in the power transmission system that transmits power from the input shaft 10 to the output shaft 20. It may function as a dynamic vibration absorber that absorbs vibration. For example, the second spring 42 and the second intermediate shaft 32 may vibrate in a phase opposite to the vibration generated in the power transmission system to absorb the vibration of the power transmission system.

FIG. 4 is a diagram for explaining a second engagement state. FIG. 4 shows a specific example of the second engaging state realized by the vibration reducing device 100 of FIG. In the second engaging state, the engaging mechanism 50 engages the first intermediate shaft 31 and the second intermediate shaft 32. For example, the engaging mechanism 50 mechanically connects the first intermediate shaft 31 and the second intermediate shaft 32. In the second engaging state, the first intermediate shaft 31 and the output shaft 20 are not engaged by the engaging mechanism 50.

Therefore, in the second engaged state, for example, as illustrated in FIG. 3, the input shaft 10 is transferred to the output shaft 20 via the first spring 41, the first intermediate shaft 31, the second intermediate shaft 32, and the second spring 42. A path for transmitting power is formed. In the second engaged state, both the first spring 41 and the second spring 42 are interposed in the power transmission system from the input shaft 10 to the output shaft 20, and the power is transmitted more than in the above-mentioned first engaged state. The rigidity of the system is reduced. Therefore, in the second engaged state, the level of vibration generated in the power transmission system that transmits power from the input shaft 10 to the output shaft 20 can be lowered as compared with the first engaged state.

FIG. 5 is a diagram showing a specific example of vibration damping characteristics. FIG. 5 illustrates the result of deriving the characteristics of the vibration generated in the vehicle equipped with the vibration reduction device 100 of FIG. 2 by numerical simulation. In FIG. 5, the horizontal axis represents the frequency of the excitation torque input to the vehicle, and the vertical axis represents the vibration level. Further, in FIG. 5, the characteristic shown by the solid line is the characteristic of the vibration damped by the damping characteristic realized in the first engaged state (FIG. 3), and the characteristic shown by the broken line is the characteristic shown by the second engaged state (FIG. 3). It is a characteristic of vibration damped by the damping characteristic realized in 4).

The vibration reduction device 100 mounted on a vehicle is roughly classified into two frequency bands, which require different vibration damping characteristics. For example, it is desirable that the vibration damping characteristics differ from each other in the first frequency band and the second frequency band.

The first frequency band is a region where the frequency of the excitation torque is relatively high, and it is desirable to make the vibration level as low as possible in this region. This is, for example, to prevent torque vibration generated by a power source such as an engine from being transmitted to the drive shaft as much as possible when the vehicle is running at a constant vehicle speed. One of the specific examples of the first frequency band is the "frequency band used during non-acceleration" illustrated in FIG.

The second frequency band is a frequency band in which torque generated by a power source such as an engine must be quickly transmitted to a drive shaft when accelerating a vehicle. One of the specific examples of the second frequency band is the “frequency band used during acceleration” illustrated in FIG.

Comparing the vibration levels of the first engaged state and the second engaged state in the "frequency band used during non-acceleration" illustrated in FIG. 5, two springs (first spring 41 and second spring 42 in FIG. 4) are compared. It can be seen that the vibration level can be lowered by the characteristic (broken line) corresponding to the second engaged state in which the power is transmitted via). However, even in the characteristic (solid line) corresponding to the first engaged state, the point A (near the point A) corresponding to the resonance point of the dynamic vibration absorber (the second spring 42 and the second intermediate shaft 32 in FIG. 3) is included. It can be seen that the vibration level is suppressed to the same level as in the second engaged state.

Further, even in the "frequency band used during acceleration" illustrated in FIG. 5, there is a region in which the vibration level is suppressed lower in the second engaged state than in the first engaged state. However, if the vibration level is kept low, even if the driver of the vehicle depresses the accelerator pedal to accelerate the vehicle, the vehicle may not accelerate quickly. Therefore, in the "frequency band used during acceleration" in which the vehicle is to be accelerated, the first engaged state having a relatively high vibration level is desirable.

Therefore, the vibration reducing device 100 of the specific example shown in FIG. 2 selectively uses the first engaged state and the second engaged state according to the traveling state of the vehicle, thereby vibrating according to the traveling state of the vehicle. Achieves the damping characteristics of.

FIG. 6 is a diagram (flow chart) showing a specific example 1 of control according to the traveling state of the vehicle. FIG. 6 illustrates a specific example of the control executed by the vibration reduction device 100 of FIG.

In Specific Example 1 shown in FIG. 6, it is first confirmed whether or not there is a request for acceleration (S601). For example, when it is detected that the driver of the vehicle depresses the accelerator pedal to accelerate the vehicle, the vibration reduction device 100 determines that the traveling state of the vehicle is in the accelerating state due to a request for acceleration. On the other hand, for example, when it is not detected that the accelerator pedal is depressed, the vibration reduction device 100 determines that the traveling state of the vehicle is in the non-acceleration state because there is no request for acceleration.

When there is a request for acceleration and it is determined that the traveling state of the vehicle is in the acceleration state, the vibration reduction device 100 sets the engagement mechanism 50 in the first engagement state (S602). That is, when it is determined that the traveling state of the vehicle is in the acceleration state, the first engaged state capable of transmitting power more quickly than in the case of the second engaged state is selected. Thereby, for example, when the driver depresses the accelerator pedal for the purpose of accelerating the vehicle, the vehicle can be accelerated more quickly than in the case of the second engaged state.

On the other hand, when it is determined that the traveling state of the vehicle is in the non-acceleration state without the request for acceleration, the vibration reduction device 100 puts the engagement mechanism 50 in the second engagement state (S603). That is, when it is determined that the running state of the vehicle is in the non-accelerated state, the second engaged state capable of lowering the level of vibration generated in the power transmission system is selected as compared with the case of the first engaged state. Will be done. As a result, for example, when there is no request for acceleration from the driver, the vibration of the vehicle is suppressed and the riding comfort of the vehicle is improved as compared with the case of the first engaged state.

FIG. 7 is a diagram (flow chart) showing a specific example 2 of control according to the traveling state of the vehicle. FIG. 7 illustrates a specific example of the control executed by the vibration reduction device 100 of FIG.

Also in Specific Example 2 shown in FIG. 7, it is first confirmed whether or not there is a request for acceleration (S701). For example, when it is detected that the driver depresses the accelerator pedal, the vibration reduction device 100 determines that the vehicle is in the acceleration state due to the request for acceleration. On the other hand, for example, when it is not detected that the accelerator pedal is depressed, the vibration reduction device 100 determines that the traveling state of the vehicle is in the non-acceleration state because there is no request for acceleration.

When there is a request for acceleration and it is determined that the traveling state of the vehicle is in the acceleration state, the vibration reduction device 100 sets the engagement mechanism 50 in the first engagement state (S702). Thereby, for example, when the driver depresses the accelerator pedal, the vehicle can be accelerated more quickly than in the case of the second engaged state.

On the other hand, when it is determined that the traveling state of the vehicle is in the non-acceleration state without the request for acceleration, it is confirmed whether or not the resonance point of the dynamic vibration absorber can be used (S703). Then, when the resonance point of the dynamic vibration absorber can be used, the vibration reduction device 100 puts the engagement mechanism 50 in the first engagement state (S702). As described with reference to FIG. 5, even with the characteristics (solid line) corresponding to the first engaged state, A corresponding to the resonance point of the dynamic vibration absorber (second spring 42 and second intermediate shaft 32 in FIG. 3). At the point (which may include the vicinity of point A), the vibration level can be suppressed to the same level as in the second engaged state.

On the other hand, when the resonance point of the dynamic vibration absorber cannot be used, the vibration reduction device 100 puts the engagement mechanism 50 in the second engagement state (S704). That is, when the running state of the vehicle is in the non-acceleration state and the resonance point of the dynamic vibration absorber cannot be used, the level of vibration generated in the power transmission system can be lowered as compared with the first engagement state. The engagement state is selected. As a result, for example, even when the resonance point of the dynamic vibration absorber cannot be used, it is possible to suppress the vibration of the vehicle and improve the riding comfort of the vehicle.

Although the preferred embodiments of the present invention have been described above, the above-described embodiments are merely examples in all respects, and do not limit the scope of the present invention. The present invention includes various modified forms without departing from its essence.

10 input shaft, 20 output shaft, 31 1st intermediate shaft, 32 2nd intermediate shaft, 41 1st spring, 42 2nd spring, 50 engagement mechanism, 100 vibration reduction device, 200 power source, 300 transmission, 400 drive axis.

Claims (5)

A vibration reduction device that reduces vibration in the power transmission path that transmits the power to drive the vehicle from the input side to the output side.
It has an engagement mechanism that changes the damping characteristics of vibration in the power transmission path by selectively engaging one of the plurality of axes on the output side with one axis on the input side. ,
By selecting one shaft on the output side that is engaged with one shaft on the input side according to the running state of the vehicle, the damping characteristic of vibration in the power transmission path is set to the running state of the vehicle. Corresponding damping characteristics,
A vibration reduction device characterized by this. In the vibration reduction device according to claim 1,
The engaging mechanism selectively engages one of the plurality of shafts on the output side with one shaft on the input side to change the spring constant in the power transmission path. Change the damping characteristics of vibration in the power transmission path,
A vibration reduction device characterized by this. In the vibration reducing device according to claim 1 or 2.
An input shaft into which the power obtained from the power source of the vehicle is input, and
A first intermediate shaft connected to the input shaft via a first spring,
A second intermediate shaft that is selectively engaged with the first intermediate shaft by the engaging mechanism,
An output shaft that is connected to the second intermediate shaft via a second spring and is selectively engaged with the first intermediate shaft by the engaging mechanism.
Have,
The engaging mechanism is a dual clutch type engaging mechanism that selectively engages the second intermediate shaft or the output shaft with the first intermediate shaft.
A vibration reduction device characterized by this. In the vibration reduction device according to claim 3,
When it is determined that the traveling state of the vehicle is in the accelerating state, the first intermediate shaft and the output shaft are engaged by the engaging mechanism, so that the first spring and the first spring are engaged from the input shaft. The power transmission path for transmitting power to the output shaft via the intermediate shaft is formed.
When it is determined that the traveling state of the vehicle is in the non-accelerated state, the engaging mechanism engages the first intermediate shaft with the second intermediate shaft, whereby the input shaft is connected to the first spring. The power transmission path for transmitting power to the output shaft via the first intermediate shaft, the second intermediate shaft, and the second spring is formed.
A vibration reduction device characterized by this. In the vibration reducing device according to claim 3 or 4.
By engaging the first intermediate shaft with the output shaft by the engaging mechanism, the power transmission path for transmitting power from the input shaft to the output shaft via the first spring and the first intermediate shaft is provided. The second spring and the second intermediate shaft formed and connected to the output shaft absorb the vibration of the power transmission path.
A vibration reduction device characterized by this.