JPS61220924A - Vibration control device for vehicle - Google Patents

Abstract

PURPOSE:To effectively reduce the vibration of a vehicle body, by predicting the vibration mode of a vehicle body in accordance with the rotational speed of an engine and the weight of the vehicle body, and by controlling an actuator for applying damping force to the vehicle body in accordance with the result. CONSTITUTION:An engine rotational speed detecting circuit 8 is connected to an engine ignition pulse terminal 7, and a control circuit 9 in a control section 18 obtains a waveform having an amplitude and a phase which correspond to the engine rotational speed detected by the circuit 8. This waveform is compensated in accordance with the weight of a vehicle body detected by a weight detecting circuit 13 connected to a strain gage weight detector 12, and is then amplified by a power amplifier circuit 10, and thereafter is delivered to an actuator 6 which is constituted such that electromagnetic force that is generated when a coil 63 is energized, is transmitted to a casing 68 fixed to the vehicle body through a coil support 64. Thus, it is possible to aim at cancelling out torque variations caused by the rotation of the engine 1 with the use of the force from the actuator 6 to reduce the vibration of the vehicle body 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration control device for a vehicle that reduces uiDP of a vehicle body caused by fluctuations in output torque as the engine rotates.

[Conventional technology]

One of the important technical issues in vehicles such as automobiles is the pursuit of comfortable vehicles with excellent ride comfort and vibration resistance.

In order to improve ride comfort, we have taken measures such as installing a damping force control device for the shock absorber that supports the car body, and adding a vibration absorption function to the mount mechanism that supports the engine to reduce car body vibration. ing.

However, with a horizontally mounted engine, FF (front engine,
In front drive (front drive) systems, the engine's drive reaction torque is particularly large, and its direction matches the direction of vibration of the vehicle body, so fluctuating torque from the engine is transmitted via the engine mount, causing excessive vibration of the vehicle body. Excited problems surface.

Therefore, the engine mount must satisfy the following conditions. In other words, in areas where drive reaction torque is large, the engine mount must be made rigid to limit the amount of displacement of the engine and exhaust system such as the muffler, whereas in areas where torque is relatively small in the idling and mid-to-high rotation ranges, The mount needs to have low rigidity to provide vibration isolation. It is extremely difficult to achieve these contradictory requirements at a high level, and if the natural frequency of the bending mode vibration of the car body is close to or coincides with the idle link rotation speed range, the vibration of the car body becomes large and the ride becomes uncomfortable. There is a problem that the value decreases.

Reducing vehicle body vibration, including the engine mount, is an important technical issue in improving vehicle ride comfort and comfort. In particular, in vehicles that use a FF drive system with a horizontally mounted engine, the natural frequency of the vehicle body is close to or exists in the idle link rotation speed region, and furthermore, the direction of the fluctuating torque coincides with the vibration direction of the vehicle body. Excessive vibrations were excited in the car body, and ride quality and comfort were significantly reduced.

Figure 7 shows the vibration generation mechanism of a vehicle.
i) Front engine mount elastically supporting uF2F)%(
3) is the rear engine mount that supports the rear side,
(4) is the vehicle body, and the engine (1) is attached to the vehicle body (4) via the engine rotation speed (2) and (3). By the way, in a horizontally mounted engine, the engine (
1) A plurality of cylinders are arranged and arranged perpendicular to the direction transverse to the vehicle body (4), that is, the longitudinal direction.

For this reason, the behavior of the engine (1) is such that rocking vibrations about the drive shaft are excited in response to fluctuating torque due to pressure fluctuations in the cylinder in the direction of the arrow.

On the other hand, the vibration characteristics of the car body (4) include a natural frequency that vibrates in an elastic mode in which the entire car body bends and deforms, as shown by the broken line.
Usually 25H1 (medium 1500/min)] exists.

In particular, in the idling speed range (1200 to 1600 explosions/min for 4 cylinders) where the frequency of the rocking vibration of the engine (1) and the natural frequency of the vehicle body match or are close to each other, the vehicle body is subject to excessive vibration due to the resonance phenomenon. Vibrations are excited and transmitted to the seat, reducing passenger comfort and comfort, and causing physical and mental pain to the occupants.

On the other hand, prior to filing this application, the present applicant has provided an imaging control device that suppresses imaging of structures such as bridges (for example, in Japanese Patent Application Laid-Open No. 57-041098). , detects the vibration of the object to be suppressed, operates a damping device based on this detection output, and actively applies vibration control force according to the vibration characteristics of the object structure. This has been achieved.

[Problem that the invention seeks to solve]

However, a vehicle allocation device has not yet been realized. Furthermore, since the above-mentioned photographic attenuation device forms feedback loops in the signal, there is a risk of oscillation.

This invention was made considering these circumstances,
Focusing on the fact that the vehicle body imaging caused by fluctuations in the engine's output torque corresponds to the engine rotation speed, by detecting the engine rotation speed, we can cancel the vehicle body vibration that is predicted to occur. Drive the actuator,
Control and apply damping force to the car body, and the car body! The object of the present invention is to provide a vehicle vibration control device that can detect the amount of vibration and respond to changes in vehicle weight, efficiently reduce vehicle body vibration, and improve ride quality and comfort. It is.

[Means for solving problems]

The vehicle vibration control device according to the present invention includes: an engine rotation speed detection device that is attached to the vehicle body and detects the rotation speed of the engine; a weight detection device that is attached to the vehicle body and that detects the weight of the vehicle body; The control unit includes an actuator that applies force, and a control unit that predicts the vibration mode of the vehicle body based on the ejection signals from the engine rotation speed detection device and the weight detection device, and drives the actuator based on the results. In this invention, after referring to a table stored in advance, depending on the engine speed and vehicle weight,
The system generates a signal with the optimal amplitude and phase to cancel car body vibrations, and drives an actuator to reduce grass vibrations.

(Example〕 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram of a vibration control device according to an embodiment of the present invention. In the figure, (6) is an actuator attached to the vehicle body (4), (7) is an engine ignition pulse terminal that detects engine rotation, and (8) is an engine rotation speed detection terminal connected to this terminal (7). The circuit (9) is a control circuit that generates a signal to pivot the actuator (6) in response to the signal from the engine rotation speed detection circuit (8), and ul amplifies this signal to drive the actuator (6). This power amplifier circuit constitutes a control section (g) together with the control circuit (9). (2) is the strain gauge weight detector, and (to) is the weight detection circuit. FIG. 3 is a longitudinal cross-sectional view of an electrodynamic linear actuator that applies vibration force to the vehicle body (4). In the figure, 61) is a permanent magnet, - is a cylindrical yoke, and the movable mass object αυ consists of this yoke Q and a permanent magnet 1m). - is the coil, - is the coil support that supports the coil, - is the support spring arranged at the upper and lower ends of the yoke - and holds the yoke 4, - is the guide rod that passes through the yoke 4, and is the upper and lower part of the yoke 4. With a slide bearing fixed to the end, it slides along a guide rod, and one wheel is linearly driven by the vertical force tube. - is the casing.

To explain the operation of the above-mentioned linear actuator (6), the permanent magnet r51 is magnetized in the radial direction and fixed to the yoke ring, forming a magnetic circuit, and a predetermined magnetic flux density is generated in the gap where the coil branch is inserted. .

As a result, the power amplifier circuit V0 (see Figure 1)
When more current is supplied, an electromagnetic force is generated between the coil 1 and the permanent magnet Iη. At this time, the electromagnetic force generated in the coil is transmitted to the casing fixed to the vehicle body (4) via the coil support, and acts on the vehicle body (4).

On the other hand, the electromagnetic force generated in the permanent magnet is balanced by the sum of the restoring force of the support spring supporting the yoke ring and the inertial force of the movable mass object (b). These mechanical models are shown in FIG.

Rd is the spring constant of the support spring. U is an electromagnetic force acting between the coil ring and the permanent magnet 6'D, and a vibration damping force T, which is the sum of the electromagnetic force U and the restoring force of the support spring (2), acts on the vehicle body (4). The support spring also serves to ensure the neutral position of the yoke.

Next, the operation of the entire imaging control device will be explained. In FIG. 1, the control circuit (9) calculates the engine speed from signals obtained from the engine ignition pulse terminal (7) and the engine speed detection circuit (8). By the way, the characteristics of car body vibration with respect to engine speed are as shown in Figure 4, for example.
In both (b), the horizontal axis represents the engine speed, and the vertical axis represents the amplitude of the vehicle body vibration in (a) and the phase of the vehicle body vibration in φn, which is a nine-line diagram. Figure 5 shows the characteristics when the vehicle weight changes, such as the number of passengers and the loaded weight.
The diagram αQ in b) is the diagram shown in FIGS. 4(a) and (b), respectively, and the diagrams (g) and (g) in FIG.
The diagram aη in b) is a diagram corrected by vehicle weight detection. In the zero control circuit (9), the characteristics are opposite to those in the same diagram, that is, the amplitude is the same and the phase is 180° compared to the vehicle body vibration. A control table with different values as shown in Table 1 is stored, and this table is referred to according to the calculated number of revolutions and superposition, and a waveform having the respective amplitude and phase is output.

In other words, when the number of rotations is RPM '1 and the weight is Ml, a waveform with amplitude All and phase Fil is output, and when the weight is the same Ml and the number of rotations changes to RPMIX, the amplitude becomes A.
At nt, the phase changes the output waveform to Pnl. This waveform is power amplified by the power amplifier circuit Q (I in FIG. 1), and force is applied to the vehicle body (4) by the actuator (6).

Therefore, the vehicle body (4) receives two forces: torque fluctuations due to engine rotation and forces from the actuator (6), but as mentioned above, the latter is a force with opposite characteristics to the former, so the two cancel each other out, resulting in This is equivalent to not applying any force that causes vibration to the vehicle body, and the vibration of the vehicle body (4) is reduced.

Table 1 Next, the control operation in the control circuit (9) will be explained with reference to the flowchart of FIG. First, the engine speed is calculated at the PI based on a signal from the engine speed detection circuit. Next, it is checked whether the engine speed determined in P2 is included in the control table. If it is not in the table, it is determined that no control is necessary, and the device is stopped at P5. On the other hand, if it is included in the table, the weight from the weight detection circuit is further calculated in P8, and the amplitude and phase t-i corresponding to the rotation speed and weight are calculated in P4! ! ! Output the protruding waveform. The output waveform is applied to the next stage power amplification circuit α0 (FIG. 1).

In the above embodiment, the engine ignition pulse is used as a means for detecting the engine rotation speed. However, focusing on the fact that 1797 rotations corresponds to the car body vibration, a vibration pickup is used to detect the car body vibration. may be detected to obtain the engine speed. Alternatively, a pulse signal may be detected from a one-rotation sensor using the rotation of the engine crankshaft.

Furthermore, in the above embodiment, the strain gauge (2) for detecting weight is attached to the vehicle body (4), but it may also be attached to the suspension to detect weight. In the example, the vibration reduction effect of the entire vehicle body has been described, but the vibration reduction effect may be applied only to a part of the vehicle body such as the steering wheel or the seat, and the same effect as in the above embodiment can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, the vehicle body vibration is predicted from the engine rotation speed and the Ji amount, and the actuator is configured to cancel the force applied from the engine to the vehicle body, so the vibration reduction effect is large and the signal Since no feedback loop is formed, there is no need to worry about oscillation, and stable operation can be achieved.

[Brief explanation of drawings]

FIG. 1 is a system configuration diagram of a vehicle imaging control device according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view of an actuator according to an embodiment of the present invention, and FIG. 8 is a mechanical model diagram of the actuator. Figure 4 shows the vibration characteristics of the car body with respect to the engine rotational speed, (a) is a diagram showing the relationship between amplitude and rotational speed, (b) is a diagram showing the relationship between phase and rotational speed, and Fig. 5 The figure is a diagram showing changes in unit vibration characteristics due to weight.
FIG. 6 is a flowchart showing the operation of the control circuit, and FIG. 7 is an explanatory diagram showing the mechanism by which vehicle body vibration occurs. (1)...Carrot, (4)...Car body, (6)...
・Actuator, (7)...Engine ignition Hals terminal% (8)...Engine speed detection circuit, (2)・
・・Strain gauge (lit detector), (to)・°・・control unit. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] (1) An engine rotation speed detection device that detects the rotation speed of the engine attached to the vehicle body, a weight detection device that detects the weight of the vehicle body, an actuator that is attached to the vehicle body and applies a damping force to the vehicle body, and the engine A vibration control device for a vehicle, comprising: a control section that predicts a vibration mode of a vehicle body based on detection signals from a rotation speed detection device and a weight detection device, and drives an actuator based on the results.