JPH0134824B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle vibration control device for improving riding comfort. Conventionally, as a vibration control method for a vehicle, a method has been developed in which a fluid actuation mechanism for control is attached to the spring system, and the vibration acceleration of the vehicle body is electrically detected and used as control input to operate the front air fluid actuation mechanism. It's coming. This method has the characteristic that the body support springs maintain the reference position of the body and reduce the response at the natural frequency determined by the body mass and the support springs. The effect of delay is significant, making it difficult to reduce response. In particular, when using an air system such as an air cylinder or an air bag as a fluid actuation mechanism, the response of the air servo valve that controls the amount of air using an electrical signal is poor, and currently the corner frequency is 2~2.
It is a delay element of about 3 Hz. On the other hand, a normal vehicle has a natural frequency of vibration mode called oscillation (up and down, pitching, yawing, lower center rolling, upper center rolling) in the range of 0.8 to 2 Hz, and at the same time has a vibration mode around 5 Hz due to the vibration of the bogie's axle spring and the mass of the bogie. Therefore, when the natural frequency of the bogie is dominated by 10 Hz or more, bending vibration modes of the car body as an elastic body exist in the vertical and horizontal directions, and in general, the frequency is 6 to 20 Hz in the vertical direction and 4 in the horizontal direction.
Considering that vibrations of ~15Hz have a negative effect on ride comfort, it is important to reduce vibrations over a wide frequency range. On the other hand, in the conventional vibration control device described above, no consideration is given to measures against abnormalities in the electrical system. Therefore, it is desirable to construct a vibration control device for a vehicle that suppresses vibrations over a wide frequency range as described above, and at the same time does not deteriorate riding comfort even in the event of an abnormality in the electrical system, such as a power outage or failure of the electrical circuit. is an extremely important issue. In view of the above points, the present invention sufficiently reduces vibrations over a wide frequency range, especially in response to shaking, and at the same time significantly improves riding comfort with small vibrations even at high frequencies. The object of the present invention is to provide a vibration control device for a vehicle that can ensure ride comfort. The key point of the present invention is that a fluid operating mechanism such as a hydraulic cylinder and a double-acting air cylinder is attached to the spring that supports the vehicle body, and the output of a vibration detector that electrically detects vehicle vibration is compensated for by a control circuit. , configured to operate a servo valve according to the output of the control circuit to perform feedback control of the fluid operating mechanism,
For high frequencies where the position delay of the servo valve and fluid actuating mechanism cannot be compensated for by the control circuit described above, the gain of the electrical system is reduced, and the damping effect (specific to the fluid system) of the servo valve and fluid actuating mechanism itself is The damping coefficient ratio for the vehicle body support system specific to the fluid system, which can be defined as detailed later based on the system damping that exists even when the electric signal is not guided to the servo valve), the vehicle body mass, and the spring constant of the support spring, is 0.15 or less. This is what happened. In other words, in addition to reducing the response by effectively exerting an effect on the support springs at high frequencies, even if the control signal is interrupted due to an abnormality in the electrical system, the inherent vibration, which is determined by the spring constant of the support springs and the mass of the vehicle body, In order to suppress vibrations within limits, the damping coefficient ratio of the fluid system to the vehicle body support system was set at 0.05 or higher. The second point of the present invention is that when considering the vibration mode of a multi-degree-of-freedom system in which fluid operating mechanisms are arranged in the vertical direction between the vehicle body and the front and rear bogies, and in the horizontal and horizontal directions, the vehicle body support system unique to the fluid system in the yawing mode The horizontal horizontal fluid operating mechanism and the servo valve that operates it are configured so that the damping coefficient ratio for the vehicle body support system specific to the fluid system in the vertical vibration mode is 0.05 to 0.15.
The fluid operating mechanism in the vertical direction and the servo valve that operates the mechanism are configured so that the angle becomes 0.05 to 0.15. Furthermore, the third point of the present invention is that the control circuit that compensates for the vibration detection signal and transmits it to the servo valve has the ability to detect an abnormality in the electric system, eliminating the input to the servo valve in the event of an abnormality, and simultaneously A device was installed to increase the inherent damping of the fluid system, which consists of servo valves, to prevent deterioration in riding comfort due to vibrations. The present invention will be described in detail below with reference to some examples. FIG. 1 is a block diagram showing a vibration control device for a vehicle according to the present invention, FIG. 2 is a circuit diagram showing an outline of the air servo valve in FIG. 1, and FIG. 3 is a main configuration of the air servo valve. FIG. 2 is a cross-sectional view showing the structure of a relay amplifier as a component. In Figure 1, 1 is the car body, 2 is a spring that supports the car body 1, 3 is an air cylinder that is a fluid operating mechanism attached to the spring 2, and 4 is a bogie, which in this figure is an excitation generator that directly transmits track irregularities. We will treat it as a source. Reference numeral 5 denotes a vibration detector, which in this embodiment is composed of an acceleration pickup 6 and a detector 7. Reference numeral 8 denotes a control circuit, which is composed of a compensation circuit 9 and a servo amplifier 10. Reference numeral 11 denotes an air servo valve which supplies air supplied from a current source 12 to the air cylinder 3 by current input from the servo amplifier 10 of the control circuit 8 .
supply to. In FIG. 2, numeral 13 indicates two relay amplifiers provided in the air servo valve 11 so as to correspond to each air chamber of the air cylinder 3, and a nozzle 14 is attached thereto. Reference numeral 15 denotes a flapper provided corresponding to the nozzle 14 of the relay amplifier 13 , and the flapper 15 is attached to be swingable about a support point 16. 17 is a zero point adjustment spring for the flapper 15, and 18 is a gain adjustment spring. 19 is a permanent magnet, and 20 is a coil provided corresponding to the permanent magnet 19. The permanent magnet 19 and the coil 20 are provided on both sides of the support point 16 of the flapper 15, and the flapper is controlled by a control signal from the control circuit 8 . 15. The operation of the vehicle vibration control device configured as described above will be explained. The vehicle body 1 receives the vibrational vertical displacement _ZO from the vibration excitation side (bogie 4 in this example), resulting in a vibrational displacement _ZB.
, the acceleration Z¨B is detected as an electrical signal by the vibration detector 5 , and after _being amplified by the control circuit 8 by compensating the gain and phase for the frequency,
The air servo valve 11 is driven. air servo valve 1
1 includes two sets of coils 20, permanent magnet 19, and nozzle 1
4 and a relay amplifier 13 , and a control circuit 8
The two sets of coils 20 are excited in mutually opposite directions according to the output current, and the flapper 15 is moved. At this time,
Since the relay amplifier 13 injects a portion of the supply air from the air source 12 from the nozzle 14 to the flapper 15, the supply air is supplied to both chambers of the supply cylinder 3 in opposite directions (or exhaust). Therefore, due to the pressure difference between the two chambers of the air cylinder 3, control can be performed to eliminate the vibration _acceleration Z¨B of the vehicle body. At this time, inside the air servo valve 11 , the flapper 15 is moved by an electric signal, and the valve 25 is moved via the nozzle 14, which naturally causes a delay. Especially in the case of a pneumatic servo valve, since air is highly compressible, this The phase lag is significant, and currently it is a first-order lag element with a corner frequency of 2 to 3 Hz. On the other hand, in the vibration control device configured in this way, the air in the air cylinder 3 enters and exits through the gap opened by the valve 25 of the relay amplifier 13 , so the fluid system of only the air servo valve 11 and the air cylinder 3 is reduced. It has a unique damping function. In this embodiment, the damping coefficient ratio ζ' for the vehicle body support system specific to the fluid system, which can be defined as described later, is set to 0.15 or less to reduce vibrations of the vehicle body at high frequencies beyond the capability of the air servo valve 11 . In addition, even if the electrical systems such as the vibration detector 5 and the control circuit 8 fail and control is not performed, the fluid system is designed to provide the necessary minimum damping effect to the vehicle body vibration. The damping coefficient ratio ζ' is set to 0.05 or more. The cross-sectional area of the air cylinder 3 is A (cm ³ ), the internal resistance of the air servo valve 11 is r _P (Kgf・s/cm ⁵ ), and the equivalent capacity of the air cylinder 3 is Cs (cm ⁵ /Kgf) [Cs=Vs /
1.4Ps, Vs is the volume of the air cylinder 3 and piping (cm ³ ), Ps is the supply pressure (Kgf/cm ³ )], and the car body 1
The mass of is m (Kg), and the spring constant of spring 2 is k (Kgf/
cm), then the response magnification of the response displacement Z _B of the vehicle body to the excitation displacement Z _O is τ = Z _B / Z _O. In the case of air system only, τ = Z _B / Z _O = r _P (A ² + kCs) S+k/mS ² +{r _P CsmS ² +r _P (A ² kCs}
It is expressed as S+k. Here, S is a Laplace operator. On the other hand, in a general passive vibration system that provides damping using a damper without providing a control cylinder, the damping coefficient of the damper is C (Kgf・S/cm).
Then, as is well known, the response magnification τ and the damping coefficient ratio ζ are Therefore, the equivalent damping coefficient ratio ζ in the case of only the air system in this embodiment described above is approximated as follows at the natural frequency ω = √ determined by the spring constant k and the car body mass m (Substituting S = jω , j ² =-1). Here, the value of _rP is approximately determined in order to obtain stability of the air servo valve 11 itself, and in this embodiment, it is set to 0.0015 (Kgfs/cm ⁵ ). Also, since ζ' is proportional to the square of the cross-sectional area A of the air cylinder 3,
It is proportional to the fourth power of the inner diameter of the air cylinder 3. Therefore, in this embodiment, the diameter of the air cylinder 3 is approximately 100 mm, and 0.05<ζ'<0.15 is achieved. FIG. 4 shows the frequency characteristics showing the response of the vehicle body 1 during control in this embodiment, and for comparison, ζ=
The response of the passive vibration system with the spring and damper set to 0.2 is also shown by the broken line. In the figure, the inner diameter of the air cylinder 3 is changed to ζ' = 0.15, 0.05, respectively.
This is the response characteristic of the control system when This makes it possible to reduce the response even at frequencies around 10Hz.
Figure 5 shows the frequency characteristics of the response of the vehicle body 1 when the electrical system signal becomes abnormal and the electrical system does not operate and becomes only the fluid system. The response of the passive vibration system is shown by the dashed line. ′, ′ are respectively ζ′=
In the case of 0.15 and 0.05, the characteristics above 5Hz are almost the fourth
The characteristics are the same as those shown in the figure.
At the resonance point of 1.3Hz, ζ′=0.15 and τ=3.7,
When ζ′=0.05, τ=8.7. As described above, according to this embodiment, the vibrations, especially those caused by shaking, are sufficiently reduced over a wide frequency range, and at the same time, the vibrations are small even at high frequencies, so the riding comfort is significantly improved. It is possible to configure a vibration control device for a vehicle that can ensure necessary ride comfort even in abnormal situations. In this embodiment, a double-acting air cylinder is used as the fluid operating mechanism, but an air bag may also be used, or a hydraulic cylinder may be used using a hydraulic servo valve. In the case of a hydraulic system, unlike an air system in which the vehicle itself already has an air source for opening and closing doors, etc., it is necessary to mount a hydraulic source on the vehicle, but since its responsiveness is high, this example The aforementioned effect around 10 Hz can be similarly exhibited at 30 to 50 Hz. Further, in this embodiment, the acceleration of the vehicle body is used as the detection signal, but the same control can be performed even if the vibration acceleration of the bogie is detected by changing the compensation content in the control circuit. It is of course possible to detect the relative displacement between the vehicle body and the bogie, or to detect and control each of these vibrations. 6 to 8 show an embodiment in which the present invention is applied to a vehicle constituting a multi-degree-of-freedom system, where 1 is a vehicle body, 2a and 2b are springs that support the vehicle body, and 1 is a vehicle body.
It is installed on a trolley 4 at the front and rear of the vehicle.
Note that the springs 2a and 2b have elasticity also in the horizontal direction like air springs. 41 is an axial spring of the truck 4, 42 is a wheel, and 43 is a track. 3
a, 3b, 3y are air cylinders which are fluid operating mechanisms for control, and the air cylinders 3a, 3b are connected to the vehicle body 1.
and the trolley 4, respectively, in the vertical direction. Also, air cylinder 3y
is installed in the horizontal left and right direction at approximately the center position between the vehicle body 1 and the bogie 4. Reference numerals 6a, 6b, and 6y are acceleration pickups that are provided corresponding to the mounting positions of the air cylinders 3a, 3b, and 3y, respectively, and detect vibration acceleration in the same direction as the operating direction of the air cylinders 3a, 3b, and 3y. The detection results of the acceleration pickups 6a, 6b, 6y are transmitted to the corresponding detectors, and the detection results of the acceleration pickups 6a, 6b, 6y are transmitted to the corresponding detectors, and are sent to the air cylinders 3a, 3y via the control circuit.
b, 3y are configured to be controlled independently. (Detector and control circuit diagrams are not shown in Figures 6 to 8.) In such a configuration, the yaw of the vehicle body is The damping coefficient ratio for the vehicle body support system specific to the fluid system in the vibration mode is ζ′ = 0.05
~0.15, the front and rear air cylinders 3y and the air cylinders 3 arranged horizontally in the horizontal direction
Configure the air servo valve provided at y. Also,
The bogies 4 are arranged in the vertical direction so that the damping coefficient ratio inherent to the fluid system in the vertical vibration mode of the vehicle body is ζ' _Z = 0.05 to 0.15 when the front and rear bogies 4 are subjected to excitation that displaces in the vertical direction in the same phase. Front and rear air cylinders 3
a, 3b and air servo valves provided corresponding to the air cylinders 3a, 3b. In the figure, Z _B and y _B indicate vibration in each direction, φ indicates a rolling angle, ψ indicates a yawing angle, and θ indicates a pitching angle. Figures 9 to 11 show a vibration control device configured in this manner, and the vehicle's yawing excitation ψ ₀ , pitching excitation θ ₀ , and rolling excitation φ ₀ with ζ' = ζ' _Z = 0.1. The vehicle body's yaw angle response magnification (τ =
ψ _B /ψ ₀ ), pitching angle response magnification (τ = θ _B /
θ ₀ ) and rolling angle response magnification (τ = ψ _B /φ ₀ ). The frequency characteristics shown by the broken line in the figure are the characteristics of a passive vibration system using a conventional spring/damper, shown for comparison. From these results, in this example, it is possible to reduce the response at the natural frequency called oscillation in each vibration mode, and at the same time, it is possible to further reduce vibrations around 10 Hz than before. Therefore, it is possible to provide a vehicle in which the ride comfort is significantly improved and the necessary ride comfort can be ensured even in the event of an abnormality in the electrical system. In the second embodiment, control air cylinders 3a and 3b are also provided in the vertical direction, but control air cylinders 3a and 3b are provided in the horizontal and lateral directions in order to reduce the yawing vibration unique to railway vehicles, which is currently the most problematic. It is also possible to configure a vibration system by providing an air cylinder 3y and providing a conventional damper in the vertical direction. This case has the advantage of being inexpensive and capable of reducing the desired yawing vibration. As mentioned above, the damping coefficient ratio ζ′ of a fluid system is largely dependent on the inner diameter of the air cylinder, and in order to achieve ζ ₄ ′ = 0.05 to 0.15 in a railway vehicle, the inner diameter of the air cylinder in the horizontal left and right direction must be 100 to 150 mm. It is best to set the inner diameter of the air cylinder in the vertical direction to 80 to 120 mm _and
= 0.05 to 0.15 is suitable for the stability of the air servo valve. Another embodiment of the present invention will be described with reference to FIG. In the figures, the same reference numerals as those in the above embodiment indicate the same members. 51 is a comparator provided in the control circuit 8 ;
52 is an abnormal value setter connected to the comparator 51; 53 is an abnormality alarm connected to the comparator; the vibration detection result from the detector 7 and the value set in the abnormal value setter 52 are combined. When the comparator 51 determines that there is an abnormality, the abnormality alarm 53 is activated. As in the above configuration, a comparator 51, an abnormal value setting device 52, and an abnormality alarm 53 are provided to provide the electrical system with abnormality processing ability. That is, when the output of the vibration detector 7 exceeds the set value of the abnormal value setting device 52, the output of the comparator 51 to the compensation circuit 9 is stopped, a signal is output to the abnormality alarm 53, and the lamp is turned on. or sound an alarm buzzer. Therefore, according to this configuration, a predetermined ride comfort can be ensured not only when an abnormality occurs such as a simple disconnection of the power supply, but also when an abnormality signal is generated due to a failure in the control circuit or the like. Next, another embodiment of the present invention is shown in FIG. In this embodiment, in addition to the configuration shown in FIG. 12, a proportional pressure control valve 54 is provided between the air source 12 and the air servo valve 11, and a comparator 5
If an abnormality is detected in step 1, the output to the compensation circuit 9 is stopped and at the same time a signal is given to the proportional pressure control valve 54 to increase the supply pressure to the air servo valve 11 . As a result, the internal resistance r _P in equation (a) can be increased somewhat. Therefore, it is possible to increase the damping inherent in the air system during an abnormality, and to reduce vibrations at the resonance point during an abnormality.
In this embodiment, in order to increase the damping inherent in the air system in the event of an abnormality in the electrical system, means are taken to increase the supply pressure to the air servo valve .
This can also be achieved by providing a throttle between the air cylinder 1 and the air cylinder 3 and increasing the throttle based on the output of the comparator 51. Another embodiment of the invention is shown in FIG. This embodiment is different from the embodiment shown in FIG. 13 in that the comparator 55 is operated by the output signal of the servo amplifier 10. Therefore, the set value of the abnormal value setter 56 is naturally different from that of the previous embodiment. According to this application example, since the output signal to the air servo valve 11 can be directly managed, the abnormality detection ability can be increased. Another example of application of the present invention is shown in FIG. In this embodiment, the A/D converter is an A/D converter, 60 is a microcomputer, and 61 is a D/A converter.The A/D converter 59 inputs the detected vibration acceleration as a digital signal to the microcomputer 60. While compensating and amplifying the signal and driving the air servo valve 11 through the D/A converter 61, the microcomputer 60 also detects an abnormality and can serve as the comparator described above. As explained above, according to the present invention, over a wide frequency range, especially from 0.8 to
Excellent vehicle vibration that sufficiently reduces vibrations at 2 Hz and at the same time has small vibrations even at high frequencies, which can significantly improve ride comfort and ensure the necessary ride comfort even in the event of an electrical system abnormality. A control device can be proposed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the vehicle vibration control device of the present invention, FIG. 2 is a circuit diagram showing an outline of the air servo valve in FIG. 1, and FIG. 3 is a sectional view of a relay amplifier. Fig. 4 is a graph showing the frequency characteristics showing the response of the vehicle body during control in the above embodiment, and Fig. 5 shows the frequency characteristics showing the response when the electrical system signal becomes abnormal and only the fluid system becomes active. 6 is a front view showing an embodiment in which the present invention is applied to a vehicle configuring a multi-degree-of-freedom system, FIG. 7 is a plan view of FIG. 6, and FIG. 8 is a side view of FIG. 6. Figures 9 to 11 are graphs showing the frequency characteristics of the vehicle body response to yawing, pitching and rolling vibrations, Figures 12 and 13
14 and 15 are block diagrams showing other embodiments of the vehicle vibration control device according to the present invention. DESCRIPTION OF SYMBOLS 1... Vehicle body, 2... Spring, 3... Air cylinder, 4... Truck, 5 ... Vibration detector, 8 ... Control circuit, 11 ... Air servo valve, 50 ... Malfunction detection circuit, 54... …Proportional pressure control valve.

Claims (1)

[Scope of Claims] 1. A fluid operating mechanism is attached to a spring that supports the vehicle body, and includes a vibration detector for detecting vibrations of the vehicle, a control circuit, and a servo valve, and the output of the vibration detector is compensated by the control circuit. A vibration control device for a vehicle that operates a servo valve to control the internal pressure of the fluid operating mechanism, characterized in that a damping coefficient ratio specific to the fluid system to the vehicle body support system is set to 0.05 to 0.15. Device. 2. In claim 1, the fluid operating mechanism is located between the front and rear bogies and the vehicle body in two directions in the width direction of the vehicle body.
A vibration detector is provided for detecting vibration in the vertical direction at the position where the fluid actuation mechanism is installed on the vehicle body, and the control circuit and the servo valve are respectively provided corresponding to the fluid actuation mechanism, and the vibration detector is arranged in a vertical vibration mode. A vibration control device for a vehicle, characterized in that a damping coefficient ratio for a vehicle body support system specific to a fluid system is set to 0.05 to 0.15. 3. In claim 1 or 2, the fluid operating mechanism is disposed between the front and rear bogies and the vehicle body, respectively, in the horizontal left and right direction, and the fluid operating mechanism is disposed in the horizontal left and right direction at a position on the vehicle body where the fluid operating mechanism is installed. A vibration detector is provided to detect the vibration of the fluid system, and the control circuit and the servo valve are provided corresponding to each fluid operating mechanism, and the damping coefficient ratio for the vehicle body support system specific to the fluid system in the yawing mode is set to 0.05 to 0.05.
0.15. 4. A vehicle according to claim 1, characterized in that the control system is provided with a malfunction prevention device that detects a malfunction of the control system and prevents the output from the control system from being transmitted to the servo valve. Vibration control device. 5. The vibration control device for a vehicle according to claim 4, further comprising means for increasing a damping coefficient ratio of the fluid system specific to the vehicle body support system when the malfunction prevention device is activated.